3,053 research outputs found

    Osteoblastoma del sacro. A propósito de dos casos clínicos.

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    El osteoblastoma es un tumor óseo primitivo de frecuente localización en los elementos posteriores de la columna vertebral, aunque raro en el sacro. Se presentan dos osteoblastomas del sacro, con un seguimiento medio de ocho años, tratados mediante resección intralesional que, sin morbilidad, deparó un excelente resultado. El curetaje sería un procedimiento de resección válido en osteoblastomas sacros no agresivos, si bien obliga a un seguimiento prolongado del paciente para vigilar la posibilidad de recidivas locales.Osteoblastoma is a primary neoplasm of bone fre- quently located in the posterior elements of the spine, alt- hough rarely affecting the sacrum. Two cases in this location are reported, with a mean follow-up of eight years, treated with an intralesional resection that, without any morbidity, has provided an excellent result. Curettage should be a valid re- section procedure for nonagressive osteoblastomas of the sacrum, although it makes necessary a long follow-up in or- der to watch over the possibility of a local recurrence

    Deformación plástica del antebrazo: revisión y caso clínico

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    La deformidad plástica de un hueso es una rara entidad, que en ocasiones pasa desapercibida. Se trata de una lesión típica del niño, con un hueso más elástico que los adultos. La mayoría de las deformidades plásticas del antebrazo se producen por caídas con el brazo en extensión, causando deformidad, dolor y una limitación de la pronosupinación. Para reducir la curvatura del hueso se precisan fuerzas contrarias a las que produjeron la lesión, mantenidas en el tiempo. En niños menores de 4 años, con enorme capacidad de remodelación, sólo grandes deformidades >20º deberían ser reducidas. En los mayores de 10 años, con escaso potencial remodelador, deben manipularse aquellas angulaciones >10-15º. La mayor complicación derivada de una mala reducción es la limitación de la pronosupinación, que en la mayoría de las ocasiones no altera la funcionalidad de la extremidad.Plastic bowing of a bone is a rare entity that some- times goes unnoticed. It’s a typical injury in children, who have more elastic bones than adults. Most of the plastic bowing of the forearm take place by falls with an outstretched arm, causing deformities, pain and a limitation of pronation and supination. In order to reduce the curvature of the bone, opposing forces to those that produced the injury are needed, maintained for a long time. In children younger than 4 years, with an enormous remodelling capacity, only great deformi- ties >20º should be reduced. For those older than 10 years, with little remodelling capacity, angulations >10-15º must be manipulated. The greatest complication derived from a bad reduction is the limitation of the pronation and supination, which in most cases does not modify the functionality of the extremity

    Nuestra experiencia con el minivástago femoral de disco a compresión y el cotilo Hedrocel (tantalio)

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    Durante los años 2000 a 2002 intervinimos 18 pacientes de artrosis o necrosis sintomática de cadera, con minivástago de fijación metafisiaria de Disco a Compresión (Sulzer) y cotilo monobloque de tantalio Hedrocel (Zimmer), con par de fricción alúmina-polietileno. La edad media de los pacientes fue de 46,7 años (rango 35-61), y el seguimiento medio de 42 meses. La valoración clínica se realizó con la escala de Merle D'Augbigné Postel obteniendo 38,8% de resultados excelentes, 22,2 de resultados buenos, 11,1% regulares y 27,4% malos (5 casos). Cuatro casos necesitaron reintervención por aflojamiento del tallo femoral. No hubo ningún fracaso del cotilo. La sustitución protésica de la cadera en los pacientes jóvenes requieren soluciones con la menor resección del hueso, pero este modelo de tallo femoral, no da un resultado satisfactorio, por lo que lo hemos abandonado.Between 2000 2002 we treated 18 patients with symptomatic osteoarthritis or osteonechrosis of hip, with uncemneted Thrust Plate Protesis (Sulzer) and tantalium acetabular componente Hedrocel (Zimmer), with ceramic-pol- yethylene pair. The average age of the patients was 46,7 years (range:35-61), and the average follow-up of 42 months. Clinical evaluation was done with Merle D'Augbigné Postel's scale obtaining 38,8 % of excellent results, 22,2 % of good results, 11,1 % fair and 27,4 % poor (5 cases). Four cases needed re-operation for loosening of the femoral stem. There was no failure of the acetabular component. The hip artrhroplasty in the young patients need solutions with the minor resection of bone, but this model of femoral stem does not give a satisfactory result, therefore we have abandoned it

    Factorizing Kernel Operators

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    Consider an operator T : X--->Y between Banach function spaces having adequate order continuity and Fatou properties. Assume that T can be factorized through a Banach space as T =SR, where R and the adjoint of S are p-th power and q-th power factorable, respectively. Then a canonical factorization scheme can be given for T. We show that it provides a tool for analyzing T that becomes specially useful for the case of kernel operators. In particular, we show that this square factorization scheme for T is equivalent to some inequalities for the bilinear form defined by T. Kernel operators are studied from this point of view.Support of the Ministerio de Economia y Competitividad under project # MTM2012-36740-C02-02 (Spain) is gratefully acknowledged.Galdames, O.; Sánchez Pérez, EA. (2013). Factorizing Kernel Operators. Integral Equations and Operator Theory. 75(1):13-29. https://doi.org/10.1007/s00020-012-2019-zS1329751Bennett C., Sharpley R.: Interpolation of Operators. Academic Press, Boston (1988)Calabuig J.M., Delgado O., Sánchez-Pérez E.A.: Factorizing operators on Banach function spaces through spaces of multiplication operators. J. Math. Anal. Appl. 364, 88–103 (2010)Defant A.: Variants of the Maurey-Rosenthal theorem for quasi Köthe function spaces. Positivity 5, 153–175 (2001)Defant A., Sánchez Pérez E.A.: Maurey-Rosenthal factorization of positive operators and convexity. J. Math. Anal. Appl. 297, 771–790 (2004)Diestel, J., Uhl, J.J.: Vector Measures. Mathematical Surveys, vol. 15. American Mathematical Society, Providence (1977)Fernández A., Mayoral F., Naranjo F., Sáez C., Sánchez-Pérez E.A.: Spaces of integrable functions with respect to a vector measure and factorizations through L p and Hilbert spaces. J. Math. Anal. Appl. 330, 1249–1263 (2007)Galdames O., Sánchez Pérez E.A.: Optimal range theorems for operators with p-th power factorable adjoints. Banach J. Math. Anal. 6(1), 63–71 (2012)Lindenstrauss J., Tzafriri L.: Classical Banach Spaces II. Springer, Berlin (1979)Okada, S., Ricker, W.J., Sánchez Pérez, E.A.: Optimal Domain and Integral Extension of Operators acting in Function Spaces. Operator Theory: Adv. Appl., vol. 180. Birkhäuser, Basel (2008)Zaanen, A.C.: Integration, 2nd revised edn. North Holland, Amsterdam; Interscience, New York (1967

    Tectonic Control on Sedimentary Dynamics in Intraplate Oceanic Settings: A Geomorphological Image of the Eastern Canary Basin and Insights on its Middle-Upper Miocene to Quaternary Volcano-Tectonic-Sedimentary Evolution

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    This paper integrates sedimentary, tectonic and volcanic geological processes inside a model of volcano-tectonic activity in oceanic intraplate domains related to rifted continental margins. The study case, the eastern Canary Basin (NE Atlantic), is one of the few places in the world where giant MDTs and Quaternary volcanic and hydrothermal edifices take place in intraplate domains. In this paper, we analyse how two structural systems (WNW-ESE and NNE-SSW) matching with the oceanic fabric control the location of volcanic systems, seafloor tectonic reliefs and subsequently the distribution of main sedimentary systems. Linear turbidite channels, debris flow lobes and the lateral continuity of structural and volcanic reliefs follow a WNW-ESE trend matching the tracks of the oceanic fracture zones. Furthermore, escarpments, anticline axes and volcanic ridges follow a NNE-SSW trend matching normal faults delimiting blocks of oceanic basement. The morpho-structural analysis of all the above geomorphological features shows evidence of a volcanic and tectonic activity from the middle–upper Miocene to the Lower–Middle Pleistocene spread over the whole of the eastern Canary Basin that reached the western Canary Islands. This reactivation changes the paradigm in the seamount province of Canary Islands reported inactive since Cretaceous. A tecto-sedimentary model is proposed for this period of time that can be applied in other intraplate domains of the world. A tectonic uplift in the study area with a thermal anomaly triggered volcanic and hydrothermal activity and the subsequent flank collapse and emplacement of mass transport deposits on the Western Canary Slope. Furthermore, this uplift reactivated the normal basement faults, both trending WNW-ESE and NNE-SSW, generating folds and faults that control the location of turbidite channels, escarpments, mass transport deposits and volcanic edifices.Versión del edito

    Evidencias de actividad tectónica contemporánea en el sector oriental de la plataforma continental y talud superior del Golfo de Cádiz (SO de la Península Ibérica)

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    La interpretación de una serie de registros de sísmica de muy alta resolución con ecosonda paramétrica TOPAS obtenidos en las campañas CADHYS0713, INDEMARES/CHICA1011 y ARSA 0313 en el sector oriental de la plataforma continental y talud superior del Golfo de Cádiz entre los 50 y los 400 m de profundidad, ha permitido identificar una serie de estructuras tectónicas que deforman tanto los depósitos de edad Holoceno y Pleistoceno Superior, como la superficie del fondo . Estas unidades estratigráficas se han identificado sobre la Superficie Transgresiva Posglacial, datada en 18 ka. Las principales estructuras identificadas son fallas normales y fallas inversas, cuya actividad se ha relacionado con fases de elevación de estructuras diapíricas de naturaleza salina que se extienden desde zonas emergidas hasta zonas distales del margen continental del Golfo de Cádiz.Very high resolution parametric echosounder (TOPAS) data interpretation obtained during CADHYS0713, INDEMARES/CHICA1011 and ARSA0313 cruises along the middle, external shelf and upper slope of the eastern Gulf of Cadiz between 50 and 400 m depth has allowed us the identification of several active tectonic structures acting since the Holocene. To date this activiy, it have been identified along the study area three postglacial discontinuities, Postglacial Trangressive Surface (TS) of 18 ky BP; the maximum flooding surface (MFS) of 6.5 ky; and the 3.5 ky Mid highstand deposits surface (MHS). Active normal and reverse faults have been identified whose recent activity is closely linked to the uplift episodes of salt diapirs structures from onshore to distal areas of the continental margin.Versión del edito

    Joint tumor bud–MMP/TIMP count at the invasive front improves the prognostic evaluation of invasive breast carcinoma

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    Producción CientíficaBackground: Tumor budding is a histological phenomenon consisting of the formation of small clusters of one to five undifferentiated malignant cells detached from the main tumor mass which are observed in the tumor stroma. In the present study, we investigated the prognostic significance of tumor budding in breast cancer and its relationship with the expressions of matrix metalloproteases (MMPs) and their tissue inhibitors (TIMPs). Methods: The number of buds was counted in whole-tissue sections from 153 patients with invasive ductal carcinomas who underwent a long follow-up period. In addition, an immunohistochemical study of MMP-9, -11, and -14 TIMP-1 and -2 expression by cell types at the invasive tumor front was carried out. Results: There was a wide variability in the number of buds among tumors, ranging from 0 to 28 (median = 5). Tumor budding count ≥ 4 was the optimal cut-off to predict both relapse-free and overall survival. High-grade tumor budding was associated with MMP/TIMP expression by cancer-associated fibroblasts. In addition, we found that the combination of tumor budding grade with MMP/TIMP expression by stromal cells, and especially with MMP-11 expression by mononuclear inflammatory cells, significantly improved the prognostic evaluation. Conclusion: High-grade tumor budding is associated with a more aggressive tumor phenotype, which, combined with MMP/TIMP expression by stromal cells at the invasive front of the tumor, identifies patients with poor prognosis.Instituto de Salud Carlos III y Fondo Europeo de Desarrollo Regional (FEDER) - (grant PI17/02236 and DTS19-00109

    Biochemical Characterization of a Trypanosomatid Isolated from the Plant Amaranthus retroflexus

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    A protozoan flagelate has recently been isolated from Amaranthus retroflexus. This plant grows near economically important crops in southeastern Spain, which are known to be parasitized by Phytomonas spp. The present study focuses on the characterization of the energy metabolism of this new isolate. These flagellates utilize glucose efficiently as their primary energy source, although they are unable to completely degrade it. They excrete ethanol, acetate, glycine, and succinate in lower amount, as well as ammonium. The presence of glycosomes was indicated by the early enzymes of the glycolytic pathway, one enzyme of the glycerol pathway (glycerol kinase), and malate dehydrogenase. No evidence of a fully functional citric-acid cycle was found. In the absence of catalase activity, these flagellates showed significant superoxide dismutase activity located in the glycosomal and cytosolic fractions. These trypanosomes, despite being morphologically and metabolically similar to other Phytomonas isolated from the same area, showed significant differences, suggesting that they are phylogenetically different species

    Recent results in nuclear astrophysics at the n_TOF facility at CERN

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    The neutron time of flight (n_TOF) facility at CERN is a spallation source characterized by a white neutron spectrum. The innovative features of the facility, in the two experimental areas, (20 m and 185 m), allow for an accurate determination of the neutron cross section for radioactive samples or for isotopes with small neutron capture cross section, of interest for Nuclear Astrophysics. The recent results obtained at n_TOF facility are presented
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