50 research outputs found

    La cuenca cámbrica del Grupo Mesón en el Noroeste Argentino: desarrollo estratigráfico y paleogeográfico

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    Los depósitos siliciclásticos del Grupo Mesón (Cámbrico) constituyen el primer antecedente de las ingresiones marinas paleozoicas desarrolladas en el noroeste argentino. La distribución actual de estos depósitos está restringida al ámbito de la Cordillera Oriental argentina. La sedimentación habría ocurrido en una cuenca intracratónica angosta y elongada en sentido Norte-Sur. El Grupo Mesón yace sobre la Formación Puncoviscana e intrusivos asociados (Proterozoico Superior- Eocámbrico) en relación de discordancia angular, y son cubiertos, tanto por el Grupo Santa Victoria y equivalentes (Ordovícico Inferior) como por el Grupo Salta (Cretácico-Eoceno) a través de una discordancia erosiva. El Grupo Mesón está integrado por tres formaciones: Lizoite (inferior), Campanario (media) y Chalhualmayoc (superior). La sedimentación habría ocurrido en una plataforma marina somera dominada por corrientes de mareas con algunos eventos de tormenta.The siliciclastic sediments of the Mesón Group represent the Cambrian of the NW Argentine; it is the initial stage of the Paleozoic marine transgressions that had place in the Central Andes . During the Middle-Upper Cambrian, in the northwest Argentine an intracratonic basin developed between the Arequipa-Antofalla craton, to the east, and Terreno Pampeano, to the west, in the present Eastern Cordillera. The Mesón Group is constituted by three formations: Lizoite (lower), Campanario (middle) and Chalhualmayoc (upper). The Mesón Group overlies the Puncoviscana Fo rmation and granitic rocks (Late Proterozoic - Early Cambrian) with a marked unconformity, and the Cambrian is followed, through an discontinuity, by the overlying fossiliferous Lower Ordovician strata or by the Cretaceous Salta Group in some places of the quebrada of Humahuaca area. The facies association reveals a shallow marine depositional environment with strong evidence for tide-influenced sedimentation for the Mesón Group, reflected in the type of bedding structures and palaeocurrent orientation

    Investigation and Management of Apparently Sporadic Central Nervous System Haemangioblastoma for Evidence of Von Hippel-Lindau Disease.

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    Haemangioblastomas are rare, highly vascularised tumours that typically occur in the cerebellum, brain stem and spinal cord. Up to a third of individuals with a haemangioblastoma will have von Hippel-Lindau (VHL) disease. Individuals with haemangioblastoma and underlying VHL disease present, on average, at a younger age and frequently have a personal or family history of VHL disease-related tumours (e.g., retinal or central nervous system (CNS) haemangioblastomas, renal cell carcinoma, phaeochromocytoma). However, a subset present an apparently sporadic haemangioblastoma without other features of VHL disease. To detect such individuals, it has been recommended that genetic testing and clinical/radiological assessment for VHL disease should be offered to patients with a haemangioblastoma. To assess "real-world" clinical practice, we undertook a national survey of clinical genetics centres. All participating centres responded that they would offer genetic testing and a comprehensive assessment (ophthalmological examination and CNS and abdominal imaging) to a patient presenting with a CNS haemangioblastoma. However, for individuals who tested negative, there was variability in practice with regard to the need for continued follow-up. We then reviewed the results of follow-up surveillance in 91 such individuals seen at four centres. The risk of developing a potential VHL-related tumour (haemangioblastoma or RCC) was estimated at 10.8% at 10 years follow-up. The risks of developing a recurrent haemangioblastoma were higher in those who presented <40 years of age. In the light of these and previous findings, we propose an age-stratified protocol for surveillance of VHL-related tumours in individuals with apparently isolated haemangioblastoma.NIHR Cambridge Biomedical Research Centre, VHL Alliance UK, NIHR Manchester Biomedical Research Centre (IS-BRC-1215-20007

    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

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    Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase&nbsp;1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation&nbsp;disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age&nbsp; 6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score&nbsp; 652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc&nbsp;= 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N&nbsp;= 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in&nbsp;Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in&nbsp;Asia&nbsp;and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

    The Carboniferous MTD Complex at La Peña Canyon, Paganzo Basin (San Juan, Argentina)

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    The La Peña Canyon section (San Juan Province, western Argentina) provides outstanding examples of different varieties of mass‐transport deposits (MTDs) and related sediments, showing a wide range of lithologies (from mud to sand dominated), scales and styles of deformation (from imbricate thrusts comprising the entire thickness of the deposit down to meso‐ and microscale folding), and mechanical responses (ductile, brittle) according to the rheology of the sediment. Specific observations include (i) the amalgamation of MTDs and the recognition of amalgamation surfaces; (ii) the tendency for MTDs to make up a progressively smaller proportion of the succession as the basin fills; (iii) the progressive disaggregation and homogenization of the protolith, from clear boundaries between a muddy matrix and sandy blocks and slabs up to almost complete mixing generating a ?holomictite? (nom, nov.), via intermediate stages of peperite‐like lithologies; (iv) slow deformation contemporaneous with deposition of overlying sediments (progressive slumping), suggesting emplacement or post‐emplacement modification by creep; and (v) the tendency to find clean, structureless gravel at the sole of some larger MTDs, suggesting a mechanism for MTD sliding involving a layer of gravel with overpressured pore fluid, combining models of hydroplaning and linked cavity systems.Fil: Valdez Buso, Victoria. University of Aberdeen; Reino UnidoFil: Milana, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Sobiesiak, Matheus S.. University of the Sinos Valley; BrasilFil: Kneller, Benjamin. University of Aberdeen; Reino Unid
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