59 resultados para 462


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The clinical demand for a device to monitor Blood Pressure (BP) in ambulatory scenarios with minimal use of inflation cuffs is increasing. Based on the so-called Pulse Wave Velocity (PWV) principle, this paper introduces and evaluates a novel concept of BP monitor that can be fully integrated within a chest sensor. After a preliminary calibration, the sensor provides non-occlusive beat-by-beat estimations of Mean Arterial Pressure (MAP) by measuring the Pulse Transit Time (PTT) of arterial pressure pulses travelling from the ascending aorta towards the subcutaneous vasculature of the chest. In a cohort of 15 healthy male subjects, a total of 462 simultaneous readings consisting of reference MAP and chest PTT were acquired. Each subject was recorded at three different days: D, D+3 and D+14. Overall, the implemented protocol induced MAP values to range from 80 ± 6 mmHg in baseline, to 107 ± 9 mmHg during isometric handgrip maneuvers. Agreement between reference and chest-sensor MAP values was tested by using intraclass correlation coefficient (ICC = 0.78) and Bland-Altman analysis (mean error = 0.7 mmHg, standard deviation = 5.1 mmHg). The cumulative percentage of MAP values provided by the chest sensor falling within a range of ±5 mmHg compared to reference MAP readings was of 70%, within ±10 mmHg was of 91%, and within ±15mmHg was of 98%. These results point at the fact that the chest sensor complies with the British Hypertension Society (BHS) requirements of Grade A BP monitors, when applied to MAP readings. Grade A performance was maintained even two weeks after having performed the initial subject-dependent calibration. In conclusion, this paper introduces a sensor and a calibration strategy to perform MAP measurements at the chest. The encouraging performance of the presented technique paves the way towards an ambulatory-compliant, continuous and non-occlusive BP monitoring system.

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This introductory chapter briefly introduces a few milestones in the voluminous previous literature on semantic roles, and charts the territory in which the papers of this volume aim to make a contribution. This territory is characterized by fairly disparate conceptualizations of semantic roles and their status in theories of grammar and the lexicon, as well as by diverse and probably complementary ways of deriving or identifying them based on linguistic data. Particular attention is given to the question of how selected roles appear to relate to each other, and we preliminarily address the issue of how roles, subroles, and role complexes are best thought of in general.

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CYP2D6 is a human cytochrome P450 that is responsible for the metabolism of a large number of drugs and chemicals. Interest in CYP2D6 has largely centered on the wide interindividual variability in its catalytic activity that stems from a common genetic polymorphism in the CYP2D6 gene. Two major phenotypes exist, extensive metabolizer (EM) and poor metabolizer (PM), together with the two less studied phenotypes of ultrarapid metabolizer (UM) and intermediate metabolizer. These phenotypes are the expression of an underlying allelomorphism in CYP2D6 and are also context dependent. Several drugs that are CYP2D6 substrates display polymorphic metabolism, that is, the existence in the population of multiple phenotypes, in particular EM and PM. The most notable drugs in this regard are debrisoquine and sparteine, although there are also data for a few others, in particular, dextromethorphan and metoprolol. Many nongenetic factors can alter the expression of CYP2D6 phenotypes, the most significant of which is the presence of other drugs. In this context, the EM phenotype may not be immutable, with potential conversion into a PM phenocopy, due to significantly impaired CYP2D6 metabolism in the presence of other CYP2D6 substrates and inhibitors. This phenotype interconversion generated great concern and helped drive the movement away from phenotyping based upon drug administration to genotyping of acquired DNA samples. However, ascertaining the presence of CYP2D6 alleles in a DNA sample does not determine the metabolism and pharmacokinetics of CYP2D6 substrates in that subject: it is a forecast, much like the weather forecast and, as we all know regarding the weather, the forecast can be inaccurate at times.

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We introduce a new boundary layer formalism on the basis of which a class of exact solutions to the Navier–Stokes equations is derived. These solutions describe laminar boundary layer flows past a flat plate under the assumption of one homogeneous direction, such as the classical swept Hiemenz boundary layer (SHBL), the asymptotic suction boundary layer (ASBL) and the oblique impingement boundary layer. The linear stability of these new solutions is investigated, uncovering new results for the SHBL and the ASBL. Previously, each of these flows had been described with its own formalism and coordinate system, such that the solutions could not be transformed into each other. Using a new compound formalism, we are able to show that the ASBL is the physical limit of the SHBL with wall suction when the chordwise velocity component vanishes while the homogeneous sweep velocity is maintained. A corresponding non-dimensionalization is proposed, which allows conversion of the new Reynolds number definition to the classical ones. Linear stability analysis for the new class of solutions reveals a compound neutral surface which contains the classical neutral curves of the SHBL and the ASBL. It is shown that the linearly most unstable Görtler–Hämmerlin modes of the SHBL smoothly transform into Tollmien–Schlichting modes as the chordwise velocity vanishes. These results are useful for transition prediction of the attachment-line instability, especially concerning the use of suction to stabilize boundary layers of swept-wing aircraft.

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BACKGROUND Compliance with surgical checklist use remains an obstacle in the context of checklist implementation programs. The theory of planned behaviour was applied to analyse attitudes, perceived behaviour control, and norms as psychological antecedents of individuals' intentions to use the checklist. METHODS A cross-sectional survey study with staff (N = 866) of 10 Swiss hospitals was conducted in German and French. Group mean differences between individuals with and without managerial function were computed. Structural equation modelling and confirmatory factor analysis was applied to investigate the structural relation between attitudes, perceived behaviour control, norms, and intentions. RESULTS Significant mean differences in favour of individuals with managerial function emerged for norms, perceived behavioural control, and intentions, but not for attitudes. Attitudes and perceived behavioural control had a significant direct effect on intentions whereas norms had not. CONCLUSIONS Individuals with managerial function exhibit stronger perceived behavioural control, stronger norms, and stronger intentions. This could be applied in facilitating checklist implementation. The structural model of the theory of planned behaviour remains stable across groups, indicating a valid model to describe antecedents of intentions in the context of surgical checklist implementation.

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"Préférence communautaire" is an in-built notion of the CAP since its inception with the Treaty of Rome (1957). Its’ simple objective laid down at the Stresa Conference in 1958 is to prefer community produce over imports wherever possible, while at the same time promoting agricultural exports and FDI (“vocation exportatrice de l’Europe”). Does this contrast or correlate with the notion of “food sovereignty” which originated in 1996 as a notion of small farmer self-sufficiency (Via Campesina), and which now has found its way into the official EC discourse? Recent CAP reforms indeed seem to continue banking on border protection and on the occasional export subsidy. Nonetheless, coming together with claims to mitigate climate change, “food sovereignty” à la CAP fails to acknowledge efficiency losses at home and negative spillover effects on the right to food of food exporting developing countries. This chapter asks whether new non-tariff and domestic support measures are just new wine in the old cask of fortress Europe, together with the FDI promotion instruments of the FED and others. Might the increasing dynamics and new challenges of agricultural trade and investment lead to lower market and production shares for European farms? It concludes that in the medium term the WTO Green Box has the only legal and effective tools to promote EU agriculture and food.

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BACKGROUND The best-known cause of intolerance to fluoropyrimidines is dihydropyrimidine dehydrogenase (DPD) deficiency, which can result from deleterious polymorphisms in the gene encoding DPD (DPYD), including DPYD*2A and c.2846A>T. Three other variants-DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A-have been associated with DPD deficiency, but no definitive evidence for the clinical validity of these variants is available. The primary objective of this systematic review and meta-analysis was to assess the clinical validity of c.1679T>G, c.1236G>A/HapB3, and c.1601G>A as predictors of severe fluoropyrimidine-associated toxicity. METHODS We did a systematic review of the literature published before Dec 17, 2014, to identify cohort studies investigating associations between DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A and severe (grade ≥3) fluoropyrimidine-associated toxicity in patients treated with fluoropyrimidines (fluorouracil, capecitabine, or tegafur-uracil as single agents, in combination with other anticancer drugs, or with radiotherapy). Individual patient data were retrieved and analysed in a multivariable analysis to obtain an adjusted relative risk (RR). Effect estimates were pooled by use of a random-effects meta-analysis. The threshold for significance was set at a p value of less than 0·0167 (Bonferroni correction). FINDINGS 7365 patients from eight studies were included in the meta-analysis. DPYD c.1679T>G was significantly associated with fluoropyrimidine-associated toxicity (adjusted RR 4·40, 95% CI 2·08-9·30, p<0·0001), as was c.1236G>A/HapB3 (1·59, 1·29-1·97, p<0·0001). The association between c.1601G>A and fluoropyrimidine-associated toxicity was not significant (adjusted RR 1·52, 95% CI 0·86-2·70, p=0·15). Analysis of individual types of toxicity showed consistent associations of c.1679T>G and c.1236G>A/HapB3 with gastrointestinal toxicity (adjusted RR 5·72, 95% CI 1·40-23·33, p=0·015; and 2·04, 1·49-2·78, p<0·0001, respectively) and haematological toxicity (adjusted RR 9·76, 95% CI 3·03-31·48, p=0·00014; and 2·07, 1·17-3·68, p=0·013, respectively), but not with hand-foot syndrome. DPYD*2A and c.2846A>T were also significantly associated with severe fluoropyrimidine-associated toxicity (adjusted RR 2·85, 95% CI 1·75-4·62, p<0·0001; and 3·02, 2·22-4·10, p<0·0001, respectively). INTERPRETATION DPYD variants c.1679T>G and c.1236G>A/HapB3 are clinically relevant predictors of fluoropyrimidine-associated toxicity. Upfront screening for these variants, in addition to the established variants DPYD*2A and c.2846A>T, is recommended to improve the safety of patients with cancer treated with fluoropyrimidines. FUNDING None.

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Die Geschichte der Humangenetik stellte lange Zeit ein vernachlässigtes Gebiet der medizin- und wissenschaftshistorischen Forschung dar. Erst in jüngster Vergangenheit sind einige historische Arbeiten erschienen, die sich der Geschichte dieses medizinischen Forschungs- und Praxisfeldes widmen. Eine wichtige Forschungsfrage betrifft die Beziehung der Humangenetik zur Eugenik. Der vorliegende Beitrag greift diese Frage auf und zeigt anhand eines Schweizer Fallbeispiels zur Vererbung des Kropfes, dass zwischen der Humangenetik und der Eugenik im 20. Jahrhundert enge, aber auch widersprüchliche Beziehungen bestanden: Ergebnisse aus Vererbungsstudien widersprachen nicht selten eugenischen Postulaten, zugleich konnten aber dieselben humangenetischen Untersuchungen Visionen einer erbbiologischen Bevölkerungsüberwachung befeuern.

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Transition from pediatric to adult care in renal transplantation has emerged as a critical step in the life of a young kidney recipient. During this phase, young patients are faced with the physiological and psychological changes associated with adolescence that can lead to non-compliance and potentially graft loss. To date, there is not a unique accepted model of transition, however it has been proved that the presence of a multidisciplinary team including specialists in adolescent management and in the transition from pediatric to adult transplant care is beneficial during this at-risk phase. The goal of this team is to ensure a progressive transition of the patients according to a precise plan and time line.