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Trabajo presentado en el MRS Fall Meeting, celebrado en Boston, MA (Estados Unidos), del 29 de noviembre al 3 de diciembre de 2010, Processes of severe plastic deformation have been investigated for a wide range of ductile alloys over the past decade, generally with an objective of refining the microstructural scale, for example the grain size, but have hardly been considered for intermetallics. This presentation discusses processing of a boride-containing Fe3Al alloy using a multidirectional, high-strain and high-temperature forging technique. Iron aluminides with relatively low Al contents can be regarded as Al-rich ferritic steels with outstanding oxidation-corrosion properties. However, as for many ferritic steels, they show poor creep resistance at temperatures above about 600ºC. The deformation processing leads to a material with large grain size and refined dispersion of thermally-stable boride particles. The particles produce a large increase in creep strength under conditions of moderate stresses and low strain rates at temperatures near 700ºC. This high-strain forging technique can be seen as an intermediate processing method between conventional wrought metallurgy and mechanical-alloying powder metallurgy, whereby an initially coarse and inhomogeneous dispersion of second phase is refined and made more homogeneous, and can be considered as a useful processing technique for a wide range of particle-containing materials.

Trabajo presentado en el MRS Fall Meeting, celebrado en Boston, MA (Estados Unidos), del 29 de noviembre al 3 de diciembre de 2010, Iron aluminides show many interesting properties, but still show relatively poor ductility at room temperature and only moderate creep resistance at temperatures above about 600ºC. Processes of severe plastic deformation have been investigated for a wide range of ductile alloys over the past decade, but have hardly been considered for intermetallics. This presentation discusses two studies aimed at refining microstructure by the use of severe plastic deformation of iron aluminides. The first considers processing Fe3Al by heavy cold rolling, followed by annealing for recovery or recrystallization, with an objective of refining grain size to improve strength at the same time as ductility. The high strength and poor ductility of the work hardened material leads to a danger of cracking during rolling, which is a problem for manufacturing large quantities of healthy material. Suitable rolling and recovery treatments can, nevertheless, lead to strong materials with some plastic ductility. A different technique of multidirectional, high-strain and high-temperature forging applied to a boride-containing Fe3Al alloy produces a material with large grain size and refined dispersion of boride particles. These particles lead to a considerable increase in creep strength under conditions of moderate stresses at temperatures around 700ºC. This high-strain forging technique can be seen as an intermediate processing method between conventional wrought metallurgy and mechanical-alloying powder metallurgy. This technique offers the possibility to improve high temperature behaviour of such intermetallics containing second-phase dispersions, and can be scaled to produce large quantities of high-quality material.

The effect of Taenia hydatigena larvae vesicular concentrate (ThLVC) on the establishment of an experimental infection by Haemonchus contortus was evaluated. The lambs that received ThLVC showed a greater (P0.05) average of blood eosinophils (BE) than the lambs that did not receive ThLVC. Lambs that were only infected with H. contortus larvae showed a fecal egg count (FEC) and an adult phase (AP) number greater (P0.05) than lambs that received ThLVC prior to infection. No effect was observed in size and prolificacy of AP after the administration of ThLVC. The infection with H. contortus caused an increase (P0.05) in CD4+ lymphocytes in abomasal lymph node (ALN) and the combination of ThLVC plus the infection with H. contortus caused an increase (P0.05) in CD4+ lymphocytes in the abomasal wall (AW). In addition, a positive correlation between gamma-delta lymphocytes of ALN (r=0.73, P0.05) with the presence of AP in the abomasum was observed. The quantity of plasma cells in ALN and AW was not affected by the administration of ThLVC nor related to the resistance observed. The results shown in this work leave no doubt that ThLVC administration prior to inoculation produces eosinophilia and partially protects against the establishment of H. contortus. However, this protection is not only attributable to the role of eosinophils, since ThLVC can function stimulating other immune response cells, such as T lymphocytes, both contributing to prevent the presence of worms.

Medium energy ion scattering (MEIS), using 100 keV H+ ions, has been applied to investigate the surface relaxations involved in the Cu(4 1 0)-O phase through the measurement and simulation of a series of blocking curves. Measurements were made in six different scattering geometries that exploit the intrinsic asymmetry of the stepped surface by using the scattering plane that is perpendicular to the surface and to the [0 0 1] steps (i.e. in the [1 (4) over bar 0] azimuth). Specifically, incidence in 'up-step' and 'down-step' directions were used that are equivalent relative to the (1 0 0) terraces, but not relative to the (4 1 0) surface. A range of relaxation models were tested, investigating the influence of 16 distinct structural parameters that define surface-induced displacements perpendicular and parallel to the surface, but optimising only the eight parameters associated with movements of the outermost four Cu atom rows that lie directly at the solid/vacuum interface. Relaxations broadly similar to those found in a previous study based on X-ray diffraction and density functional theory calculations are found, although there are some significant quantitative differences. The results are also compared with relaxations previously measured on the related Cu(1 0 0)(root 2 x 2 root 2)R45 degrees-O 'missing row' structure. (C) 2010 Elsevier B.V. All rights reserved.

Ultrafme grained materials prepared by methods of severe plastic deformation appear to show good ductility for their high strength. To a large extent this ductility enhancement, for the given strength, is shown to correspond to the fracture ductility and not the uniform ductility at maximum stress. The improved fracture ductility is often due to the refinement or removal of the coarse defects that act as sites for failure nucleation. The low work hardening rate inherent to the very fine microstructures produced by severe plastic deformation essentially condemns such materials to very low uniform ductility. Stress relaxation occurring during unloading after processing, and changes of internal stresses during reloading for mechanical testing, appear to play a significant role in determining deformation behaviour near the onset of plastic flow, and this can affect the measured uniform strain. © (2010) Trans Tech Publications.

11 pages, Nanostructured coatings with variable contents of tungsten carbide (WC) and amorphous carbon (a-C) are prepared by controlling the sputtering power ratio using WC and graphite targets. XRD and TEM/ED analysis shows that increasing the C incorporation, the WC nanocrystalline phases evolve from γ-W2C to β-WC1 − x. Further C enrichment leads to a nanocomposite structure of small WC1 − x crystals dispersed in a-C matrix. The a-C at.% is estimated by XPS analysis and correlated with the observed tribo-mechanical properties. The hardness and friction properties vary from hard/high friction (36–40 GPa; μ = 0.6–0.8) to moderate-hard/low friction (16–20 GPa; μ 0.2) coatings depending on the film composition. The transition point is found for a-C content of 10 at.%. This correlates with a change from nanocrystalline WC to nanocomposite WC1 − x/a-C coatings. The overall study will help to understand the previous literature data and will serve as guide for a tailored synthesis of these WC/a-C nanocomposites., The authors are grateful to the Spanish Ministry of Science and Innovation (project No. MAT2007-66881-C02-01 and Consolider FUNCOAT CSD2008-00023), European Union (EXCELL project NMP3-CT-2005-515703) and I3 programme of CSIC for financial support. F. Hofer, B. Schaffer and W. Grogger from the Research Institute for Electron Microscopy, Graz (Austria) are acknowledged for collaborating in HRTEM analysis.

Fever in an immunocompromised patient like the transplanted subject is usually due to an overt or occult infection. Clinicians must make important decisions to find the cause of fever, and also concerning the timing and adequacy of empiric antibiotic therapy. However, occasionally, fever is not due to an infectious cause. A correct identification of its causes may avoid a needlessly prolonged course of antibiotics. Herein we have reported a kidney transplant patient with a febrile syndrome, which appeared after endovascular aortoiliac stent-graft placement, that was finally attributed to a noninfectious cause like postimplantation syndrome.

In this work, the in situ interaction between Ti-6Al-4V alloy and osteoblastic cells has been studied by electrochemical techniques as a function of time. The interaction has been monitored for cell adhesion and growth of human osteoblastic Saos-2 cells on Ti-6Al-4V samples. The study has been carried out by electrochemical techniques, e.g., studying the evolution of corrosion potential with exposure time and by electrochemical impedance spectroscopy. The impedance results have been analyzed by using different equivalent circuit models that simulate the interface state at each testing time. The adhesion of the osteoblastic cells on the Ti-6Al-4V alloy leads to surface areas with different cell coverage rates, thus showing the different responses in the impedance diagrams with time. The effect of the cells on the electrochemical response of Ti-6Al-4V alloy is clearly seen after 4 days of testing, in which two isolated and well-differentiated time constants are clearly observed. One of these is associated with the presence of the cells and the other with a passive film on the Ti-6Al-4V alloy. After 7 days of culture, the system is governed by a resistive component over a wide frequency range which is associated with an increase in the cell coverage rate on the surface due to the extracellular matrix. © 2008 Acta Materialia Inc.

The energy spectrum associated with scattering of 100 keV H+ ions from the outermost few atomic layers of Cu(111) in different scattering geometries provides direct evidence of trajectory-dependent electronic energy loss. Theoretical simulations, combining standard Monte Carlo calculations of the elastic scattering trajectories with coupled-channel calculations to describe inner-shell ionization and excitation as a function of impact parameter, reproduce the effects well and provide a means for far more complete analysis of medium-energy ion scattering data.

In this study, Mongolian gerbils were used to analyse features of Toxocara infection that included larval migration, humoral immune responses to Toxocara canis excretory–secretory antigens (TES) and aspects of host physiology. At day 10 post-infection (p.i.) most larvae were in the intestine and the lungs while later the total number of larvae was higher in the carcass tissue; the number of larvae per gram of tissue was lower elsewhere other than in the brain. Infected animals showed several neurological abnormalities, an early increase in leukocyte and neutrophil levels, two peaks of peripheral eosinophilia (5 and 40 d.p.i.) and high antibody levels against TES in the circulation and in the vitreous humor. A sequential recognition of eight T. canis larval antigens with MW from 24 to 200 kDa was detected by Western blot. The results obtained in this study further support the use of gerbils as an experimental model for systemic, ocular and cerebral toxocariasis.

A comparative study has been made of room temperature severe plastic deformation of an Al-7% Si composite, containing large Si particles, and a monolithic Al-0.5% Si with the same chemical composition as that of the composite matrix. In the composite, the large local strain gradients existing between the matrix and the coarse, undeformable, Si particles produce a much higher density of geometrically necessary dislocations which are responsible for much faster grain refinement. Annealing at 200 °C produces only small variations in grain size due to the precipitation of fine Si particles while severe deformation at the same temperature leads to a much larger grain size with much coarser precipitates. The corresponding mechanical properties have been analysed in terms of the different microstructural contributions to strengthening in both alloys. © 2007 Elsevier B.V. All rights reserved.

Una de las causas principales de lesion cerebral secundaria es la hipoxia cerebral, fundamentalmente de origen isquemico. No obstante, la oxigenacion tisular cerebral depende de multiples variables fisiologicas y la hipoxia cerebral puede ser originada por una alteracion de cualquiera de ellas. Aunque han sido desarrollados varios metodos de monitorizacion continua de la oxigenacion cerebral en pacientes neurocriticos, la medicion directa y continua de la presion de oxigeno en el tejido cerebral (PtiO2) es una realidad en el manejo de pacientes neurocriticos desde los ultimos anos. Esta tecnica destaca por su fiabilidad y valor de la informacion que proporciona. En el presente articulo se expone una revision de los aspectos mas relevantes de la monitorizacion de la PtiO2 y se propone un protocolo para su interpretacion. Este algoritmo pretende facilitar la identificacion de diferentes tipos de hipoxia cerebral y la correcta eleccion terapeutica en el complejo proceso de toma de decisiones en pacientes neurologicos criticos en riesgo de hipoxia cerebral.

Cell-penetrating peptides (CPPs) constitute a family of peptides whose unique characteristic is their ability to insert into and cross biological membranes. Cell-penetrating peptide carriers of the Pep family are amphipathic peptides which have been shown to deliver peptides and proteins into a wide variety of cells through formation of non-covalent complexes with their cargo. In this study, we have investigated the morphological features of different Pep-1/cargo complexes by scanning electron microscopy and light scattering measurements. We provide first-time evidence that biologically efficient complexes of Pep-1/p27Kip tumour suppressor physically exist in the form of discrete nanoparticles. Moreover, we have characterized the relationship between the Pep-1/cargo ratio, the size and homogeneity of the nanoparticles formed, and their efficiency in delivering the cargo into cells, and report that particle size and homogeneity is both directly dependent on the ratio of Pep-1/cargo formulations, and responsible for their biological efficiency. © 2007 Elsevier Inc. All rights reserved.

The reactivity of high-Fe containing sphalerite (Zn 1− x Fe x S), the major source of Zn, is of great interest for industrial applications. Since the initial reactivity depends on the physical and chemical properties of the surface, it is important to understand the structure of cleaved and fractured surfaces. Zn 1− x Fe x S zincblende (1 1 0) oriented samples cleaved in air and in vacuum were studied with medium energy ion scattering (MEIS) in order to study surface relaxation and reconstruction associated with the possible formation of S dimers. The experimental results are presented together with ion scattering Monte Carlo simulations that have been performed using the different models of the surface structure. The MEIS blocking patterns are different for the air- and vacuum-cleaved specimens. Models for the air-cleaved samples found S atoms in the first layer that are relaxed outwards by 0.08 A and Zn(Fe) atoms relaxed inwards by 0.51 A, with some lateral translation of both species. Results for the vacuum-cleaved sample indicate S atoms have been displaced laterally by 0.5 A at the surface. X-ray photoelectron spectroscopic (XPS) measurements provide evidence for a high binding energy species indicative of S–S bonds in the near-surface region that are consistent with the ion scattering structural data for both cleaving protocols.

Novel FeAlCr oxide dispersion strengthened intermetallics that are processed by powder metallurgy have been developed as potential biomaterials. The alloys exhibit a small grain size and a fine dispersion of yttria provides the material with a high yield strength and depending on the alloy composition good ductility (up to 5%). The biocompatibility of the alloy was assessed in comparison with commercial alumina. Saos-2 osteoblast-like cells were either challenged with mechanically alloyed particles, or seeded onto solid samples. Viability and proliferation of cells were substantially unaffected by the presence of a high concentration of particles (1 mg/mL). Solid samples of novel FeAlCr intermetallic have shown a good biocompatibility in vitro, often approaching the behavior of materials well known for their biological acceptance (e.g. alumina). It has been found that osteoblasts are able to produce ALP, a specific marker of cells with bone-forming activity. In this respect, ALUSI alloys hold the promise to be suitable substrate for bone integration. The finding of no cytotoxic effect in the presence of the alloy particles is a reliable proof of the absence of acute toxicity of the material. © 2006 Wiley Periodicals, Inc.

$100\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ ${\mathrm{H}}^{+}$ medium-energy ion scattering has been applied to investigate the surface relaxations of the clean rutile ${\mathrm{TiO}}_{2}(110)\text{\ensuremath{-}}(1\ifmmode\times\else\texttimes\fi{}1)$ surface structure. A set of blocking curves in four different incident directions show clear differences between the surface and bulk attributable to surface relaxation. Optimized values of the surface relaxation parameters to give the best fit to the surface structure are generally in quite good agreement with a recent experimental determination of this structure using quantitative low-energy electron diffraction. In particular, both solutions favor an outward relaxation of the bridging O atoms on the surface rather than the strong inward displacement favored by the only previous experimental structure determination based on surface x-ray diffraction.

Despite decades of intensive research iron aluminides remain characterised by relatively poor ductility at room temperature and low strength at high temperatures, especially under slow strain rate or creep conditions. A variety of strengthening particles has been tested for improving high temperature strength, but each has serious limitations: typical carbide precipitates are unable to resist dissolution or coarsening at high temperatures; as-solidified iron aluminides with sufficient amounts of transition elements such as Nb or Mo show heavy solidification segregation and are embrittled by a network of Laves phase; mechanical milling with stable oxides appears an excessively expensive processing route. A new iron-aluminium alloy has been developed with Zr and Cr additions that forms fine coherent precipitates even after extended annealing at temperatures as high as 900ºC. These precipitates have a complex Fe3Zr structure and form in a cube-on-cube orientation relationship in the bcc matrix. The low solubility and diffusivity of the solute, as well as the low energy, near-coherent interface ensures excellent stability of these intermetallic precipitates. Interesting strengthening is possible for this material under the relevant high temperature creep conditions.

High temperature microstructural changes are examined for two Ti-Al alloys, containing W or Nb-Mn additions. Changes of mechanical properties on annealing are related to the stability of the α/γ lamellae, which depends sensitively on whether β phase is stabilised at any temperature. W has a strong effect, first stabilising β phase, then inducing a β to γ change at lower temperatures. Its diffusivity is slow and any changes take place slowly. Mn and Nb have much milder effects and structural changes are similar to binary TiAl alloys. Property changes can still be rapid when fine scale α/γ lamellae are annealed, due to easy small-scale diffusion. © 2005 Elsevier Ltd. All rights reserved.

The energy-loss spectrum associated with scattering of 100 keV H{sup +} ions from Y atoms on Si(111) has been investigated both experimentally and theoretically. Measurements were made from Y overlayers, and from the Si(111)(1x1) two-dimensional silicide phase formed by Y on this surface, in various scattering geometries and with different surface preparations. Theoretical simulations were conducted based on calculations of the energy loss experienced in specific ion trajectories through the surface, using coupled-channel calculations to describe inner-shell ionization and excitation as a function of impact parameter. The experimental results indicate that additional broadening contributions arise from surface inhomogeneity and roughness, but for near-normal incident and outgoing trajectories the theory and experiment agree quite well. The calculations show that, even for the ideal two-dimensional silicide phase in which the Y atoms lie just below the surface, significant energy loss arises from interaction of the ions with surrounding Si atoms, leading to a complete loss of intensity at zero energy loss.

In vitro properties of a new γ-based TiAl intermetallic have been evaluated in the as-received state and after carrying out surface modifications by oxidation under two different heat treatments, namely 700 °C, 24 h and 1000 °C, 1 h. Cathodic stripping voltammetry was used to determine the concentration of Ti and Al elements released into a solution simulating the body fluids (Ringer's solution) after six months immersion. Electrochemical techniques were used to measure the corrosion resistance and the susceptibility to pitting corrosion. The results confirmed that the best material is the TiAl intermetallic pre-oxidised at 700 °C, since it produces a much lower concentration of Al and Ti ions and also exhibits the lowest passive current densities. The latter are one order of magnitude lower than those of the as-received intermetallic alloy and after pre-oxidation at 1000 °C and two orders of magnitude lower than that obtained from a conventional Ti6Al4V currently used as biomaterial. © 2004 Elsevier Ltd. All rights reserved.

The objective was to determine whether the age of patients with mild head injury and skull fracture influences the level of risk for acute intracranial injuries.A study was conducted of 156 patients with skull fracture, 60 children (aged14 years) and 96 adults, detected among 5,097 consecutive patients with mild head injury (Glasgow Coma Scale [GCS] score of 15-14 points) arriving at the Emergency Department of a Level I University Hospital Trauma Center during 1998. Acute intracranial injuries were defined as traumatic brain injuries identified by cranial computed tomography scan, excluding pneumocephalus.Compared with the children, this risk of intracranial injury was 13 times greater in the adults aged 14-54 years and 16 times greater in the over-54-year-olds. Besides age over 14 years (p0.0001), compound skull fracture (p0.001), and a GCS score of 14 (p0.001) were factors significantly associated with intracranial injury in the logistic regression analysis.Skull fracture in mild head injury implies a greater risk of intracranial injury in adults than in children.

A brief survey is presented of a range of recent and current experiments in which medium energy ion scattering has been used to study the structure of metallic surfaces and near-surface interfaces. These include: surface alloy phases on elemental metal substrates in which the presence of interface and sub-surface stacking faults are investigated (Sb on Cu(1 1 1) and Ag(1 1 1)) and the amplitude and origin of surface layer rumpling are identified (Pb on Ni(1 1 1), Sn on Ni(1 1 0), Au and Mn on Cu(1 0 0)); near-surface composition and structure of a Pt 25 Rh 75 (1 1 1) alloy surface; the early stages of oxidation and oxide growth on Ru and Ni surfaces.

CYTOMEGALOVIRUS (CMV) infection in renal transplant recipients has been related to the intensity of the immunosuppression. The introduction of mycophenolate mofetil (MMF) as a third drug combined with steroids and cyclosporine A (CyA) or tacrolimus in the immunosuppressive protocols in renal transplantation has dramatically decreased the incidence of acute rejection. However, there are few studies that describe the impact of these new MMF-based immunosuppressant therapies on infection by CMV. Here we compare the incidence of CMV infection in our program of renal transplantation in the period before and after MMF was introduced.

An iron aluminide alloy of base composition Fe-40Al has been prepared by mechanical alloying and processed using a variety of powder consolidation methods and heat treatments to produce a range of grain sizes and oxide dispersoid sizes. The strengths of these materials have been determined at room temperature and related to the various aspects of microstructure. Fine dispersoid particles may pin grain boundaries and help determine the fine grain size and contribute very significantly to the material strength. Grain size strengthening is shown to be a rather small component of the material strength, with the matrix strength being rather high for this intermetallic. The influence of other factors such as texture and the direction of application of stress (tension or compression) are also briefly discussed. © 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

Se han estudiado los propagulos fungicos existentes en el exterior y en el interior de los domicilios de pacientes con sensibilizacion a hongos con tests cutaneos positivos por duplicado con antigenos (Ags) procedentes de dos casas comerciales a los generos: Alternaria, Aspergillus, Cladosporium, Mucor y Penicillium , encontrando globalmente una correlacion del 73,03% en la presencia en el ambiente del paciente del hongo responsable de la sensibilizacion; aunque en el estudio pormenorizado no ha habido concordancia entre el orden de frecuencia en la positivizacion de los tests cutaneos ( Mucor, Alternaria, Cladosporium, Penicillium y Aspergillus ) y el mayor numero de colonias aislado ( Penicillium, Cladosporium, Alternaria, Aspergillus y Mucor ).

Objective: Describe the results obtained with a new percutaneous, intracisternal model of Subarachnoid Haemorrhage (SAH) in Wistar rats by a single injection of non-heparinised, autologous blood. Methods: Once anaesthetized the rat was fixed prone in a stereotaxic frame. After identifying the projection of the occipital bone, the needle of the stereotaxic frame aspirated towards the foramen magnum until it punctured through the atlanto-occipital membrane and obtained cerebrospinal fluid. Autologous blood (100. μl) was withdrawn from the tail and injected intracisternally. This procedure was repeated in the sham group, injecting 100. μl of isotonic saline. On the fifth day post-intervention, the rats were anaesthetized and the brain was exposed. After a lethal injection of ketamine the brain was explanted and fixed in paraformaldehyde. Gross and microscopic inspection of the slices revealed the existence or non-existence of pathological findings. Results: A total of 26 rats were operated on (13 in the SAH group/13 in the sham group). The average time between obtaining the blood and the start of the intracisternal injection was 10 (±1.2). s. The mortality rate was 16.12%. Intra- and extraparenchymal ischemic-haemorrhagic lesions were found in three animals (23.07%) - all from the SAH group - with ischemic neuronal cell injury detected in two of the three. Conclusions: The new murine model of SAH is easy to perform, with low mortality, minimally invasive, which makes it interesting for future studies on vasospasm-related delayed SAH complications. © 2012 Elsevier B.V., This study has been funded by Health Research Fund 2010 (Fondos de Investigación Sanitaria, FIS 2010) from the Instituto de Salud Carlos III, Spain.

Eruptions similar to those of lichen planus (LP) are associated with systemic diseases or have been induced by many drugs. Linear lesions as a Koebner effect are frequently found in LP but isolated long, narrow, linear lesions, which may extend the whole length of the limb, are rare though rather more common in childhood. Some cases of zonal or zosteriform LP have been described in the literature. We describe a case of LP with a linear distribution following the Blaschko embryologic lines induced by nicergoline in a 65-year-old woman with a 6-month history of a pruritic eruption of erythematoviolaceous papules on the left breast, trunk and upper limb, with histological features of LP. It would be the first case of linear LP associated with drugs.

CYTOMEGALOVIRUS (CMV) infection is one of the principal causes of morbidity in renal transplant recipients. The most important risk factor for the development of the CMV disease in these patients is serologic status prior to transplantation. Administration of potent immunosuppressive therapy, specifically antilymphocyte antibodies (ATGAM, OKT3), represents another important risk factor for the development of serious CMV disease. There is general agreement that prophylactic treatment should be used to prevent the disease in these patients; however, it is still unknown what is the best prophylactic regimen to prevent CMV-related infection and disease in these patients. Previous studies have suggested that the use of anti-CMV specific immunoglobulin (IG-CMV) or ganciclovir (GCV) can be effective in the prevention of this disease. The aim of this study was to compare the efficacy and safety of IG-CMV and GCV in the prevention of CMV disease in renal transplant recipients who receive antilymphocytic antibodies as immunosuppressive induction treatment.

Objetivo. Investigar nuestras practicas clinicas, a fin de identificar oportunidades de mejora en el manejo medicoquirurgico de las hemorragias subaracnoideas (HSA) espontaneas. Pacientes y metodos. Estudio de cohortes, longitudinal, prospectivo, de las HSA atendidas consecutivamente en los servicios de cuidados criticos y urgencias de 29 hospitales publicos de Andalucia durante 20 meses, de 2000 a 2002. Se consideraron HSA los accidentes cerebrovasculares hemorragicos agudos con este diagnostico tomografico. Se analizaron los resultados a 12 meses y el manejo asistencial (terapeutica medica y quirurgica, tecnicas diagnosticas, tiempos asistenciales y complicaciones neurologicas especificas), comparandolo con las practicas clinicas que la evidencia cientifica ha demostrado de mayor utilidad. Se catalogaron como muertes potencialmente evitables los obitos por resangrado en pacientes sin estudio arteriografico o sin exclusion del aneurisma. Resultados. Se incluyeron 506 HSA. Se perdio durante el seguimiento el 5% de la muestra. Fallecieron 155 enfermos. Las variables no modificables de riesgo independiente para la mortalidad fueron: edad, genero masculino, antecedente de hipertension arterial, coma a la recepcion hospitalaria e hidrocefalia. Las variables influenciables de riesgo independiente para fallecer resultaron ser: ausencia de analgesia urgente, carencia de diagnostico arteriografico, aparicion de deterioro neurologico isquemico y resangrado. El 20% de la mortalidad global podria considerarse potencialmente evitable. Conclusiones. Aunque la letalidad es mayoritariamente dependiente de variables medicamente no influenciables (sexo, edad, antecedentes, gravedad clinica e hidrocefalia), los decesos, en un 20%, estan asociados a factores modificables.

Objetivo. Valorar la incidencia y resultados de las hemorragias subaracnoideas (HSA) espontaneas en Andalucia. Pacientes y metodos. Estudio longitudinal, prospectivo, de las HSA asistidas en 28 hospitales de Andalucia, durante tres meses del ano 2000. Se consideraron HSA los ictus hemorragicos agudos con este diagnostico tomografico. La incidencia bruta (TB) se establecio mediante la informacion censal del Instituto Andaluz de Estadistica. Las tasas estandarizadas (TEE) se estimaron con relacion a la poblacion europea. Los resultados se valoraron al alta hospitalaria segun el GOS (del ingles, Glasgow Outcome Score) y a los 12 meses, segun el indice de Barthel (IB). Resultados. La TB por 100.000 habitantes/ano se situo en 5,7 casos y la TEE en 5,8. La comparacion de incidencias segun provincia o sexo no mostro diferencias estadisticamente significativas. El periodo de maximo riesgo corresponde al intervalo 55-74 anos (TB: 14,1). La TB y TEE de letalidad aguda coincidio en 1,5. A los 12 meses, la TB y TEE de letalidad ascendio a 1,9 por 100.000 habitantes y ano. La mortalidad se concentro de forma estadisticamente significativa (p< 0,01) entre los mayores de 65 anos; no influyo el sexo, pero si la gravedad clinica (p< 0,001) y la cuantia del sangrado (p< 0,005). Conclusiones. La incidencia de las HSA espontaneas en Andalucia se situa en tasas medias. La proporcion de resultados desfavorables es elevada, aunque similar a la de otras series. La letalidad se asocia significativamente a factores (edad, gravedad clinica y volumen de sangrado) no modificables medicamente