679 resultados para 12930-073


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In many designs for radioactive waste repositories, cement and clay will come into direct contact. The geochemical contrast between cement and clay will lead to mass fluxes across the interface, which consequently results in alteration of structural and transport properties of both materials that may affect the performance of the multi-barrier system. We present an experimental approach to study cement-clay interactions with a cell to accommodate small samples of cement and clay. The cell design allows both in situ measurement of water content across the sample using neutron radiography and measurement of transport parameters using through-diffusion tracer experiments. The aim of the high- resolution neutron radiography experiments was to monitor changes in water content (porosity) and their spatial extent. Neutron radiographs of several evolving cement-clay interfaces delivered quantitative data which allow resolving local water contents within the sample domain. In the present work we explored the uncertainties of the derived water contents with regard to various input parameters and with regard to the applied image correction procedures. Temporal variation of measurement conditions created absolute uncertainty of the water content in the order of ±0.1 (m3/m3), which could not be fully accounted for by correction procedures. Smaller relative changes in water content between two images can be derived by specific calibrations to two sample regions with different, invariant water contents.

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BACKGROUND Skull-base chondrosarcoma (ChSa) is a rare disease, and the prognostication of this disease entity is ill defined. METHODS We assessed the long-term local control (LC) results, overall survival (OS), and prognostic factors of skull-base ChSa patients treated with pencil beam scanning proton therapy (PBS PT). Seventy-seven (male, 35; 46%) patients with histologically confirmed ChSa were treated at the Paul Scherrer Institute. Median age was 38.9 years (range, 10.2-70.0y). Median delivered dose was 70.0 GyRBE (range, 64.0-76.0 GyRBE). LC, OS, and toxicity-free survival (TFS) rates were calculated using the Kaplan Meier method. RESULTS After a mean follow-up of 69.2 months (range, 4.6-190.8 mo), 6 local (7.8%) failures were observed, 2 of which were late failures. Five (6.5%) patients died. The actuarial 8-year LC and OS were 89.7% and 93.5%, respectively. Tumor volume > 25 cm(3) (P = .02), brainstem/optic apparatus compression at the time of PT (P = .04) and age >30 years (P = .08) were associated with lower rates of LC. High-grade (≥3) radiation-induced toxicity was observed in 6 (7.8%) patients. The 8-year high-grade TFS was 90.8%. A higher rate of high-grade toxicity was observed for older patients (P = .073), those with larger tumor volume (P = .069), and those treated with 5 weekly fractions (P = .069). CONCLUSIONS This is the largest PT series reporting the outcome of patients with low-grade ChSa of the skull base treated with PBS only. Our data indicate that protons are both safe and effective. Tumor volume, brainstem/optic apparatus compression, and age were prognosticators of local failures.

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BACKGROUND Acute myeloid leukaemia mainly affects elderly people, with a median age at diagnosis of around 70 years. Although about 50-60% of patients enter first complete remission upon intensive induction chemotherapy, relapse remains high and overall outcomes are disappointing. Therefore, effective post-remission therapy is urgently needed. Although often no post-remission therapy is given to elderly patients, it might include chemotherapy or allogeneic haemopoietic stem cell transplantation (HSCT) following reduced-intensity conditioning. We aimed to assess the comparative value of allogeneic HSCT with other approaches, including no post-remission therapy, in patients with acute myeloid leukaemia aged 60 years and older. METHODS For this time-dependent analysis, we used the results from four successive prospective HOVON-SAKK acute myeloid leukaemia trials. Between May 3, 2001, and Feb 5, 2010, a total of 1155 patients aged 60 years and older were entered into these trials, of whom 640 obtained a first complete remission after induction chemotherapy and were included in the analysis. Post-remission therapy consisted of allogeneic HSCT following reduced-intensity conditioning (n=97), gemtuzumab ozogamicin (n=110), chemotherapy (n=44), autologous HSCT (n=23), or no further treatment (n=366). Reduced-intensity conditioning regimens consisted of fludarabine combined with 2 Gy of total body irradiation (n=71), fludarabine with busulfan (n=10), or other regimens (n=16). A time-dependent analysis was done, in which allogeneic HSCT was compared with other types of post-remission therapy. The primary endpoint of the study was 5-year overall survival for all treatment groups, analysed by a time-dependent analysis. FINDINGS 5-year overall survival was 35% (95% CI 25-44) for patients who received an allogeneic HSCT, 21% (17-26) for those who received no additional post-remission therapy, and 26% (19-33) for patients who received either additional chemotherapy or autologous HSCT. Overall survival at 5 years was strongly affected by the European LeukemiaNET acute myeloid leukaemia risk score, with patients in the favourable risk group (n=65) having better 5-year overall survival (56% [95% CI 43-67]) than those with intermediate-risk (n=131; 23% [19-27]) or adverse-risk (n=444; 13% [8-20]) acute myeloid leukaemia. Multivariable analysis with allogeneic HSCT as a time-dependent variable showed that allogeneic HSCT was associated with better 5-year overall survival (HR 0·71 [95% CI 0·53-0·95], p=0·017) compared with non-allogeneic HSCT post-remission therapies or no post-remission therapy, especially in patients with intermediate-risk (0·82 [0·58-1·15]) or adverse-risk (0.39 [0·21-0·73]) acute myeloid leukaemia. INTERPRETATION Collectively, the results from these four trials suggest that allogeneic HSCT might be the preferred treatment approach in patients 60 years of age and older with intermediate-risk and adverse-risk acute myeloid leukaemia in first complete remission, but the comparative value should ideally be shown in a prospective randomised study. FUNDING None.

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BACKGROUND REG1 is a novel anticoagulation system consisting of pegnivacogin, an RNA aptamer inhibitor of coagulation factor IXa, and anivamersen, a complementary sequence reversal oligonucleotide. We tested the hypothesis that near complete inhibition of factor IXa with pegnivacogin during percutaneous coronary intervention, followed by partial reversal with anivamersen, would reduce ischaemic events compared with bivalirudin, without increasing bleeding. METHODS We did a randomised, open-label, active-controlled, multicentre, superiority trial to compare REG1 with bivalirudin at 225 hospitals in North America and Europe. We planned to randomly allocate 13,200 patients undergoing percutaneous coronary intervention in a 1:1 ratio to either REG1 (pegnivacogin 1 mg/kg bolus [>99% factor IXa inhibition] followed by 80% reversal with anivamersen after percutaneous coronary intervention) or bivalirudin. Exclusion criteria included ST segment elevation myocardial infarction within 48 h. The primary efficacy endpoint was the composite of all-cause death, myocardial infarction, stroke, and unplanned target lesion revascularisation by day 3 after randomisation. The principal safety endpoint was major bleeding. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, identifier NCT01848106. The trial was terminated early after enrolment of 3232 patients due to severe allergic reactions. FINDINGS 1616 patients were allocated REG1 and 1616 were assigned bivalirudin, of whom 1605 and 1601 patients, respectively, received the assigned treatment. Severe allergic reactions were reported in ten (1%) of 1605 patients receiving REG1 versus one (<1%) of 1601 patients treated with bivalirudin. The composite primary endpoint did not differ between groups, with 108 (7%) of 1616 patients assigned REG1 and 103 (6%) of 1616 allocated bivalirudin reporting a primary endpoint event (odds ratio [OR] 1·05, 95% CI 0·80-1·39; p=0·72). Major bleeding was similar between treatment groups (seven [<1%] of 1605 receiving REG1 vs two [<1%] of 1601 treated with bivalirudin; OR 3·49, 95% CI 0·73-16·82; p=0·10), but major or minor bleeding was increased with REG1 (104 [6%] vs 65 [4%]; 1·64, 1·19-2·25; p=0·002). INTERPRETATION The reversible factor IXa inhibitor REG1, as currently formulated, is associated with severe allergic reactions. Although statistical power was limited because of early termination, there was no evidence that REG1 reduced ischaemic events or bleeding compared with bivalirudin. FUNDING Regado Biosciences Inc.

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BACKGROUND Non-steroidal anti-inflammatory drugs (NSAIDs) are the backbone of osteoarthritis pain management. We aimed to assess the effectiveness of different preparations and doses of NSAIDs on osteoarthritis pain in a network meta-analysis. METHODS For this network meta-analysis, we considered randomised trials comparing any of the following interventions: NSAIDs, paracetamol, or placebo, for the treatment of osteoarthritis pain. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and the reference lists of relevant articles for trials published between Jan 1, 1980, and Feb 24, 2015, with at least 100 patients per group. The prespecified primary and secondary outcomes were pain and physical function, and were extracted in duplicate for up to seven timepoints after the start of treatment. We used an extension of multivariable Bayesian random effects models for mixed multiple treatment comparisons with a random effect at the level of trials. For the primary analysis, a random walk of first order was used to account for multiple follow-up outcome data within a trial. Preparations that used different total daily dose were considered separately in the analysis. To assess a potential dose-response relation, we used preparation-specific covariates assuming linearity on log relative dose. FINDINGS We identified 8973 manuscripts from our search, of which 74 randomised trials with a total of 58 556 patients were included in this analysis. 23 nodes concerning seven different NSAIDs or paracetamol with specific daily dose of administration or placebo were considered. All preparations, irrespective of dose, improved point estimates of pain symptoms when compared with placebo. For six interventions (diclofenac 150 mg/day, etoricoxib 30 mg/day, 60 mg/day, and 90 mg/day, and rofecoxib 25 mg/day and 50 mg/day), the probability that the difference to placebo is at or below a prespecified minimum clinically important effect for pain reduction (effect size [ES] -0·37) was at least 95%. Among maximally approved daily doses, diclofenac 150 mg/day (ES -0·57, 95% credibility interval [CrI] -0·69 to -0·46) and etoricoxib 60 mg/day (ES -0·58, -0·73 to -0·43) had the highest probability to be the best intervention, both with 100% probability to reach the minimum clinically important difference. Treatment effects increased as drug dose increased, but corresponding tests for a linear dose effect were significant only for celecoxib (p=0·030), diclofenac (p=0·031), and naproxen (p=0·026). We found no evidence that treatment effects varied over the duration of treatment. Model fit was good, and between-trial heterogeneity and inconsistency were low in all analyses. All trials were deemed to have a low risk of bias for blinding of patients. Effect estimates did not change in sensitivity analyses with two additional statistical models and accounting for methodological quality criteria in meta-regression analysis. INTERPRETATION On the basis of the available data, we see no role for single-agent paracetamol for the treatment of patients with osteoarthritis irrespective of dose. We provide sound evidence that diclofenac 150 mg/day is the most effective NSAID available at present, in terms of improving both pain and function. Nevertheless, in view of the safety profile of these drugs, physicians need to consider our results together with all known safety information when selecting the preparation and dose for individual patients. FUNDING Swiss National Science Foundation (grant number 405340-104762) and Arco Foundation, Switzerland.

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En este proyecto proponemos un análisis interpretativo del proceso de elaboración y desarrollo curricular de contenidos estadísticos para la EGB3 en la provincia de Misiones. Para ese análisis curricular, adoptamos una perspectiva procesual del currículum, que destaca la relación entre las intenciones educativas y las “realidades curriculares” que tienen lugar en las escuelas. Considerando que en ese proceso intervienen prácticas y actores diversos en el marco de diferentes ámbitos de decisión (nacional, provincial, institucional y áulico), partiremos del proyecto macrocurricular y, atravesando las diferentes concreciones del currículum, nos proponemos esclarecer las proximidades o distanciamientos que se dan, tanto entre las expectativas curriculares planteadas en los distintos niveles de formulación, como entre éstas y las prácticas de desarrollo del currículum. Simultáneamente, con el propósito de comprender las prácticas curriculares, buscaremos develar los supuestos y valores que las sustentan, esclareciendo las condiciones materiales y socio-históricas que les dan sentido. Adoptando un enfoque interpretativo, realizaremos un estudio de casos (escuelas de la provincia), usando análisis de documentos curriculares (nacionales, provinciales, institucionales y planificaciones docentes) así como entrevistas a docentes, observación y análisis de clases y/o material didáctico.

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Actualmente en Bolivia, uno de los mayores problemas en el ámbito de la salud es la incorporación del concepto de cultura a las políticas sanitarias, hecho que hizo que se crearan centros de salud denominados “interculturales”, así como el Modelo de Salud Familiar Comunitario e Intercultural. Este artículo, a través de una investigación realizada en el año 2007 en la zona altiplánica de Bolivia, pretende demostrar como el concepto de cultura está sirviendo de base para implementar políticas que no están ayudando a cambiar los deficientes índices epidemiológicos del país.

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Actividades desarrolladas durante el período: se profundizó la búsqueda bibliográfica respecto a la temática planteada en la investigación en relación a todas las dimensiones abordadas; para la elaboración del marco teórico pertinente, se efectuó una síntesis de los diferentes paradigmas y conceptos referentes a las políticas públicas, con profundización en las políticas sociales aplicadas a educación y modelos de inclusión educativa; en función de la relevancia del contexto en que se planifican y ejecutan las políticas sociales, producto del modelo de desarrollo impulsado y sus consecuencias, se efectuó una descripción de la región y más específicamente de la localidad; por otra parte se describió a partir de la presentación y análisis de los indicadores de mayor relevancia las condiciones de vida de la población, usando para ello información secundaria (Censos, Encuesta permanente de los hogares, estadísticas educativas, de salud, etc.) elaborada por diferentes organismos; se profundizó en diagnósticos referidos a educación, básicamente vinculado a calidad educativa en función de su importancia para la inclusión social base de los programas aplicados en el sistema educativo; se relevaron los programas existentes en el período de referencia 2005-2009, los ejecutados en la provincia, procediéndose a la clasificación de los mismos a partir de los objetivos, nivel al cuales van dirigidos, responsables de planificación, ejecución y financiación; se seleccionó para evaluar el impacto en las instituciones escolares y condiciones laborales de los docentes el Programa Integral para la igualdad educativa (PIIE), ya que específicamente está dirigido a la inclusión educativa y son los docentes y la escuela los responsables de su desarrollo; se efectuó una planilla de observación y una guía para la recolección de información que podrán brindar los directivos y/o docentes de la institución para la descripción de las escuelas seleccionadas, tanto en sus aspecto edilicio (tamaño, antigüedad, tipo de construcción, estado de conservación), población que atienden (número y características del alumnado), historia y organización institucional; se elaboró una segunda guía de entrevista para directivos y docentes destinadas a abordar las dimensiones de análisis de la presente investigación.