995 resultados para 657


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Vascular endothelial protein tyrosine phosphatase (VE-PTP) is an endothelial-specific receptor-type tyrosine phosphatase that associates with Tie-2 and VE-cadherin. VE-PTP gene disruption leads to embryonic lethality, vascular remodeling defects, and enlargement of vascular structures in extraembryonic tissues. We show here that antibodies against the extracellular part of VE-PTP mimic the effects of VE-PTP gene disruption exemplified by vessel enlargement in allantois explants. These effects require the presence of the angiopoietin receptor Tie-2. Analyzing the mechanism we found that anti-VE-PTP antibodies trigger endocytosis and selectively affect Tie-2-associated, but not VE-cadherin-associated VE-PTP. Dissociation of VE-PTP triggers the activation of Tie-2, leading to enhanced endothelial cell proliferation and enlargement of vascular structures through activation of Erk1/2. Importantly, the antibody effect on vessel enlargement is also observed in newborn mice. We conclude that VE-PTP is required to balance Tie-2 activity and endothelial cell proliferation, thereby controlling blood vessel development and vessel size.

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BACKGROUND There is ongoing debate on the optimal drug-eluting stent (DES) in diabetic patients with coronary artery disease. Biodegradable polymer drug-eluting stents (BP-DES) may potentially improve clinical outcomes in these high-risk patients. We sought to compare long-term outcomes in patients with diabetes treated with biodegradable polymer DES vs. durable polymer sirolimus-eluting stents (SES). METHODS We pooled individual patient-level data from 3 randomized clinical trials (ISAR-TEST 3, ISAR-TEST 4 and LEADERS) comparing biodegradable polymer DES with durable polymer SES. Clinical outcomes out to 4years were assessed. The primary end point was the composite of cardiac death, myocardial infarction and target-lesion revascularization. Secondary end points were target lesion revascularization and definite or probable stent thrombosis. RESULTS Of 1094 patients with diabetes included in the present analysis, 657 received biodegradable polymer DES and 437 durable polymer SES. At 4years, the incidence of the primary end point was similar with BP-DES versus SES (hazard ratio=0.95, 95% CI=0.74-1.21, P=0.67). Target lesion revascularization was also comparable between the groups (hazard ratio=0.89, 95% CI=0.65-1.22, P=0.47). Definite or probable stent thrombosis was significantly reduced among patients treated with BP-DES (hazard ratio=0.52, 95% CI=0.28-0.96, P=0.04), a difference driven by significantly lower stent thrombosis rates with BP-DES between 1 and 4years (hazard ratio=0.15, 95% CI=0.03-0.70, P=0.02). CONCLUSIONS In patients with diabetes, biodegradable polymer DES, compared to durable polymer SES, were associated with comparable overall clinical outcomes during follow-up to 4years. Rates of stent thrombosis were significantly lower with BP-DES.

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Over the past five decades, management of acute ST-segment elevation myocardial infarction (STEMI) has evolved substantially. Current treatment encompasses a systematic chain of network activation, antithrombotic drugs, and rapid instigation of mechanical reperfusion, although pharmacoinvasive strategies remain relevant. Secondary prevention with drugs and lifestyle modifications completes the contemporary management package. Despite a tangible improvement in outcomes, STEMI remains a frequent cause of morbidity and mortality, justifying the quest to find new therapeutic avenues. Ways to reduce delays in doing coronary angioplasty after STEMI onset include early recognition of symptoms by patients and prehospital diagnosis by paramedics so that the emergency room can be bypassed in favour of direct admission to the catheterisation laboratory. Mechanical reperfusion can be optimised by improvements to stent design, whereas visualisation of infarct size has been improved by developments in cardiac MRI. Novel treatments to modulate the inflammatory component of atherosclerosis and the vulnerable plaque include use of bioresorbable vascular scaffolds and anti-proliferative drugs. Translational efforts to improve patients' outcomes after STEMI in relation to cardioprotection, cardiac remodelling, and regeneration are also being realised. This is the third in a Series of three papers about ST-segment elevation myocardial infarction.

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BACKGROUND Patent foramen ovale (PFO) is associated with cryptogenic stroke (CS), although the pathogenicity of a discovered PFO in the setting of CS is typically unclear. Transesophageal echocardiography features such as PFO size, associated hypermobile septum, and presence of a right-to-left shunt at rest have all been proposed as markers of risk. The association of these transesophageal echocardiography features with other markers of pathogenicity has not been examined. METHODS AND RESULTS We used a recently derived score based on clinical and neuroimaging features to stratify patients with PFO and CS by the probability that their stroke is PFO-attributable. We examined whether high-risk transesophageal echocardiography features are seen more frequently in patients more likely to have had a PFO-attributable stroke (n=637) compared with those less likely to have a PFO-attributable stroke (n=657). Large physiologic shunt size was not more frequently seen among those with probable PFO-attributable strokes (odds ratio [OR], 0.92; P=0.53). The presence of neither a hypermobile septum nor a right-to-left shunt at rest was detected more often in those with a probable PFO-attributable stroke (OR, 0.80; P=0.45; OR, 1.15; P=0.11, respectively). CONCLUSIONS We found no evidence that the proposed transesophageal echocardiography risk markers of large PFO size, hypermobile septum, and presence of right-to-left shunt at rest are associated with clinical features suggesting that a CS is PFO-attributable. Additional tools to describe PFOs may be useful in helping to determine whether an observed PFO is incidental or pathogenically related to CS.

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Obesity is a major public health issue and an important contributor to the global burden of chronic disease and disability. Studies indicate that fish and omega-3 polyunsaturated fatty acids (n3-PUFA) supplements may help prevent cardiovascular and metabolic diseases. However, the effect of fish oil on body composition is still uncertain, so we performed a systematic review of randomized controlled trials and the first meta-analysis on the association between fish or fish oil intake and body composition measures. We found evidence that participants taking fish or fish oil lost 0.59 kg more body weight than controls (95% confidence interval [CI]: -0.96 to -0.21). Treatment groups lost 0.24 kg m(-2) (body mass index) more than controls (-0.40 to -0.08), and 0.49 % more body fat than controls (-0.97 to -0.01). Fish or fish oil reduced waist circumference by 0.81 cm (-1.34 to -0.28) compared with control. There was no difference for fat mass and lean body mass. Further research is needed to confirm or refute our findings and to reveal possible mechanisms by which n3-PUFAs might reduce weight.

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In a first step to obtain a proxy record of past climatic events (including the El Ni (n) over tildeo-Southern Oscillation) in the normally aseasonal tropical environment of Sabah, a radial segment from a recently fallen dipterocarp (Shorea Superba) was radiocarbon dated and subjected to carbon isotope analysis. The high-precision radiocarbon results fell into the ambiguous modern plateau where several calibrated dates can exist for each sample. Dating was achieved by wiggle matching using a Bayesian approach to calibration. Using the defined growth characteristics of Shorea superba, probability density distributions were calculated and improbable dates rejected. It was found that the tree most likely started growing around AD 1660-1685. A total of 173 apparent growth increments were measured and, therefore, it could be determined that the tree formed one ring approximately every two years. Stable carbon isotope values were obtained from resin-extracted wholewood from each ring. Carbon cycling is evident in the `juvenile effect', resulting from the assimilation of respired carbon dioxide and lower light levels below the canopy, and in the `anthropogenic effect' caused by increased industrial activity in the late-nineteenth and twentieth centuries. This study demonstrates that palaeoenvironmental information can be obtained from trees growing in aseasonal environments, where climatic conditions prevent the formation of well-defined annual rings.

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Content Distribution Networks are mandatory components of modern web architectures, with plenty of vendors offering their services. Despite its maturity, new paradigms and architecture models are still being developed in this area. Cloud Computing, on the other hand, is a more recent concept which has expanded extremely quickly, with new services being regularly added to cloud management software suites such as OpenStack. The main contribution of this paper is the architecture and the development of an open source CDN that can be provisioned in an on-demand, pay-as-you-go model thereby enabling the CDN as a Service paradigm. We describe our experience with integration of CDNaaS framework in a cloud environment, as a service for enterprise users. We emphasize the flexibility and elasticity of such a model, with each CDN instance being delivered on-demand and associated to personalized caching policies as well as an optimized choice of Points of Presence based on exact requirements of an enterprise customer. Our development is based on the framework developed in the Mobile Cloud Networking EU FP7 project, which offers its enterprise users a common framework to instantiate and control services. CDNaaS is one of the core support components in this project as is tasked to deliver different type of multimedia content to several thousands of users geographically distributed. It integrates seamlessly in the MCN service life-cycle and as such enjoys all benefits of a common design environment, allowing for an improved interoperability with the rest of the services within the MCN ecosystem.

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Aims: We conducted a pooled post hoc analysis (RESOLUTE All Comers and RESOLUTE International) of patients who had the Resolute® zotarolimus-eluting stent (R-ZES) implanted in revascularised total occlusions (TO) compared with patients treated with R-ZES for non-occluded lesions. Methods and results: Patients were divided into three groups: chronic TO (CTO; n=256), non-chronic TO (n=292), and no occlusion (n=2,941). Clinical and safety outcomes assessed through two years included target lesion failure (TLF: cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularisation) and Academic Research Consortium definite or probable stent thrombosis. The rate of TLF at two years was not significantly different among patients in the CTO (9.1%), TO (9.8%), and no occlusion (10.4%) groups (log-rank p=0.800); neither were the components of TLF. Definite or probable stent thrombosis occurred more frequently in the TO group (2.8% vs. 1.2% in the CTO and 1.1% in the group with no occlusion, p=0.027). There were 10 late and six very late stent thrombosis events. Conclusions: Apart from a higher rate of stent thrombosis in patients with TO, patients with totally occluded coronary arteries who receive revascularisation with an R-ZES have clinical outcomes comparable to those who receive a similar stent in non-occluded lesions.

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The sustainable use of common-pool resources depends on users’ behaviour with regards to appropriation and provision. Most knowledge about behaviour in such situations comes from experimental research. As experiments take place in confined environments, motivational drivers and actions in the field might differ. This paper analyses farmers’ use of common property pastures in Grindelwald, Switzerland. Binary logistic regression is applied to survey data to explore the effect of farmers’ attributes on livestock endowment, appropriation and provision behaviour. Furthermore, Q methodology is used to assess the impact of broader contextual variables on the sustainability of common property pastures. It is shown that the strongest associations exist between (a) socio-economic attributes and change in livestock endowment; (b) norms and appropriation behaviour; and (c) area and pay-off and provision behaviour. Relevant contextual variables are the economic value of the resource units, off-farm income opportunities, and the subsidy structure. We conclude that with increasing farm size farmers reduce the use and maintenance of common property. Additionally, we postulate that readiness to maintain a resource increases with appropriation activities and the net returns generated from appropriation.

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BACKGROUND: The role of laparoscopy in the setting of perforated appendicitis remains controversial. A retrospective study was conducted to evaluate the early postoperative outcomes of laparoscopic appendectomy (LA) compared to open appendectomy (OA) in patients with perforated appendicitis. METHODS: A total of 1,032 patients required an appendectomy between January 2005 and December 2009. Among these patients, 169 presented with perforated appendicitis. Operation times, length of hospital stay, overall complication rates within 30 days, and surgical site infection (SSI) rates were analyzed. RESULTS: Out of the 169 evaluated patients, 106 required LA and 63 OA. Although operation times were similar in both groups (92 ± 31 min for LA vs. 98 ± 45 for OA, p = 0.338), length of hospital stay was shorter in the LA group (6.9 ± 3.8 days vs. 11.5 ± 9.2, p < 0.001). Overall complication rates were significantly lower in the LA group (32.1 vs. 52.4 %, p < 0.001), as were incisional SSI (1.9 vs. 22.2 %, p < 0.001). Organ/space SSI rates were similar in both groups (23.6 % after LA vs. 20.6 % after OA, p = 0.657). CONCLUSIONS: For perforated appendicitis, LA results in a significantly shorter hospital stay, fewer overall postoperative complications, and fewer wound infections compared to OA. Organ/space SSI rates were similar for both procedures. LA provides a safe option for treating patients with perforated appendicitis.

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Einleitung Im Fußball entscheidet der Trainer, welche Spieler in eine Leistungsmannschaft selektioniert werden. Die Frage, nach welchen Kriterien Trainer die Spieler beurteilen und selektionieren, wurde bislang allerdings unzureichend untersucht (Williams & Reilly, 2000). In der vorliegenden qualitativen Studie wird der Frage nachgegangen, welche Talentkriterien aus Trainersicht für den späteren Erfolg im Spitzenfußball ausschlaggebend sind. Methode Interviewpartner waren sechs männliche Fußballtrainer (MAlter = 39.5; SD = 7.18), die hauptberuflich für die Nachwuchsabteilung (Altersklasse 13 – 17 Jahre) eines Schweizer Fußballvereins der höchsten nationalen Spielklasse (Super League) arbeiten und zum Zeitpunkt des Interviews mindestens die UEFA-A-Lizenz besaßen. Die Bestimmung der subjektiven Talentkriterien erfolgte mithilfe eines Interviewleitfadens, der sich an der Konstruktbestimmung der Repertory Grid Technik (vgl. Fromm, 2004) orientierte. Ausge-wertet wurden die Interviews mit einer qualitativen Inhaltsanalyse (Kvale, 1996). Ergebnisse und Diskussion Die Untersuchung zeigt, dass sich die subjektiven Talentkriterien von Trainern sprachlich differenziert erheben lassen. Die befragten Trainer formulierten jeweils sechs bis acht Talentkriterien, die Aspekte aus den Bereichen Persönlichkeit, kognitiv-perzeptuelle Fertigkeiten, konditionelle Fähigkeiten, Technik, physische Konstitution und Umfeld beinhalten. Dass einige Kriterien Aspekte mehrere dieser Bereiche beinhalten und inhaltlich nicht den Kriterien der anderen Trainer entsprechen, kann als Hinweis auf die Subjektivität und Individualität dieser Talentkriterien gedeutet werden. Beinahe die Hälfte der genannten Kriterien beinhalten Persönlichkeitsaspekte. Facetten der Leistungsmotivation wurden dabei am häufigsten genannt, gefolgt von Lernfähigkeit und Lernbereitschaft sowie anderen Aspekten wie z.B. zur Selbsteinschätzung und Zielorientierung. Die Er-gebnisse zeigen, dass die untersuchten Trainer eine differenzierte Wahrnehmung von entwicklungsförderlichen Persönlichkeitsmerkmalen haben. Die Bedeutung der Persönlichkeit aus Trainersicht für das Erreichen eines Spitzenniveaus ist vergleichbar mit den Ergebnissen vorheriger Untersuchungen (z.B. Christensen, 2009). Literatur Christensen, M. K. (2009). "An Eye for Talent": Talent Identification and the "Practical Sense" of Top-Level Soccer Coaches. Sociology of Sport Journal, 26, 365–382. Fromm, M. (2004). Introduction to the Repertory Grid Interview. Münster: Waxmann. Kvale, S. (1996). InterViews: An introduction to qualitative researching interviewing. Thousand Oaks: Sage Publications. Williams, A. M. & Reilly, T. (2000). Talent identification and development in soccer. Journal of Sports Sciences, 18, 657-667.

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Novel functionalized bis(ethylenedithio)tetrathiafulvalene (BEDT–TTF) derivatives 4 and 5 have been synthesized in good yields from cyano precursor via a cross-coupling reaction. Their redox potentials have been studied by cyclic voltammetry in a dichloromethane solution; this indicated that they are slightly weaker electron donors than BEDT–TTF. Compound 4 has been studied by X–ray crystallography; this revealed that, in the crystal, the molecules were held together by some unconventional C–H···N and C–H···S hydrogen bonds.

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The investigation and modelling of permafrost distribution, particularly in areas of discontinuous permafrost, is challenging due to spatial heterogeneity, remoteness of measurement sites and data scarcity. We have designed a strategy for standardizing different local data sets containing evidence of the presence or absence of permafrost into an inventory for the entire European Alps. With this brief communication, we present the structure and contents of this inventory. This collection of permafrost evidence not only highlights existing data and allows new analyses based on larger data sets, but also provides complementary information for an improved interpretation of monitoring results.