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1.
Sci Total Environ ; 882: 163649, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37094676

RESUMEN

The dumping of an estimated amount of 57 million tons of hazardous sulfide mine waste from 1957 to 1990 into Portmán's Bay (SE Spain) caused one of the most severe cases of persistent anthropogenic impact in Europe's costal and marine environments. The resulting mine tailings deposit completely infilled Portmán's Bay and extended seawards on the continental shelf, bearing high levels of metals and As. The present work, where Synchrotron XAS, XRF core scanner and other data are combined, reveals the simultaneous presence of arsenopyrite (FeAsS), scorodite (FeAsO4·2H2O), orpiment (As2S3) and realgar (AsS) in the submarine extension of the mine tailings deposit. In addition to arsenopyrite weathering and scorodite formation, the, the presence of realgar and orpiment is discussed, considering both potential sourcing from the exploited ores and in situ precipitation from a combination of inorganic and biologically mediated geochemical processes. Whereas the formation of scorodite relates to the oxidation of arsenopyrite, we hypothesize that the presence of orpiment and realgar is associated to scorodite dissolution and subsequent precipitation of these two minerals within the mine tailings deposit under moderately reducing conditions. The occurrence of organic debris and reduced organic sulfur compounds evidences the activity of sulfate-reducing bacteria (SRB) and provides a plausible explanation to the reactions leading to the formation of authigenic realgar and orpiment. The precipitation of these two minerals in the mine tailings, according to our hypothesis, has important consequences for As mobility since this process would reduce the release of As into the surrounding environment. Our work provides for the first time valuable hints on As speciation in a massive submarine sulfide mine tailings deposit, which is highly relevant for similar situations worldwide.

2.
Comput Methods Programs Biomed ; 208: 106262, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34260972

RESUMEN

The incidence of bone fracture has become a major clinical problem on a worldwide scale. In the past two decades there has been an increase in the use of computational tools to analyse the bone fracture problem. In several works, various study cases have been analysed to compare human and animal bone fracture healing. Unfortunately, there are not many publications about computational advances in this field and the existing approaches to the problem are usually similar. In this context, the objective of this work is the application of a diffusion problem in the model of the bone fragments resulting from fracture, working together with a mesh-growing algorithm that allows free growth of the callus depending on the established conditions, without a pre-meshed domain. The diffusion problem concerns the different biological magnitudes controlling the callus growth, among which Mesenchymal Stem Cells and chondrocytes concentrations were chosen, together with Tumour Necrosis Factor α and Bone Morphogenetic Protein as the factors influencing the velocity in the callus formation. A Finite Element approach was used to solve the corresponding diffusion problems, obtaining the concentration values along the entire domain and allowing detecting the zones in which biological magnitudes reach the necessary thresholds for callus growth. The callus growth is guided by a geometrical algorithm which performs an additional mesh generation process (self-added mesh) at each step of the iterative procedure until complete callus formation. The proposed approach was applied to different types of diaphyseal femoral fractures treated by means of intramedullary nailing. Axisymmetric models based on triangular quadratic elements were used, obtaining results in good agreement with clinical evidence of these kinds of fractures. The algorithm proposed has the advantage of a natural callus growth, without the existence of a previous mesh that may affect the conditions and direction of growth. The approach is intended for the initial phase of callus growth. Future work will address the implementation of the corresponding formulations for tissue transformation and bone remodelling in order to achieve complete fracture healing.


Asunto(s)
Fracturas del Fémur , Fijación Intramedular de Fracturas , Algoritmos , Animales , Callo Óseo , Curación de Fractura , Humanos
3.
Injury ; 51 Suppl 1: S74-S79, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32081396

RESUMEN

Femoral shaft fractures present high morbidity and important complications and consequences, being spiral fractures the most complicated from a biomechanical point of view, being unstable and without possibility of getting a good contact between nail and femoral endosteum. Femoral diaphyseal fractures are treated, usually, by means of intramedullary nailing. So, it is necessary to know the osteosynthesis stability and which locking screws combination is optimal. This work studies the use of reamed locked intramedullary nails in spiral femoral fractures located along zones 2 and 4 of wiss, depending on the spire length, corresponding to 32-A spiral type in AO/OTA classification, which represent a percentage of 23% within the total of diaphyseal fractures. A three-dimensional finite element model of the femur was developed, modeling a spiral fracture with different spiral lengths and gaps. A femoral nail was used, considering two transversal screws both at the proximal and the distal parts. The study was focused on the immediately post-operative stage, verifying the appropriate stability of the osteosynthesis. Reamed intramedullary blocked nails provide appropriate stability of femoral spiral fractures, considering global mobility of femoral head with respect to femoral condyles, relative displacements between fragments at fracture site, stresses at nail and locking screws, and stresses at cortical bone. The obtained results show that the use of blocked reamed nails in spiral femoral fractures can be considered as an appropriate surgical technique, providing sufficient stability in order to obtain an adequate fracture healing.


Asunto(s)
Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/instrumentación , Fijación Intramedular de Fracturas/métodos , Imagenología Tridimensional/métodos , Modelos Anatómicos , Fenómenos Biomecánicos , Clavos Ortopédicos , Fracturas del Fémur/fisiopatología , Análisis de Elementos Finitos , Curación de Fractura , Humanos , Masculino , Persona de Mediana Edad , Estrés Mecánico , Resultado del Tratamiento
4.
Sci Adv ; 5(10): eaav9822, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31633015

RESUMEN

Bone marrow and grease constitute an important source of nutrition and have attracted the attention of human groups since prehistoric times. Marrow consumption has been linked to immediate consumption following the procurement and removal of soft tissues. Here, we present the earliest evidence for storage and delayed consumption of bone marrow at Qesem Cave, Israel (~420 to 200 ka). By using experimental series controlling exposure time and environmental parameters, combined with chemical analyses, we evaluated bone marrow preservation. The combination of archaeological and experimental results allowed us to isolate specific marks linked to dry skin removal and determine a low rate of marrow fat degradation of up to 9 weeks of exposure. This is the earliest evidence of such previously unidentified behavior, and it offers insights into the socio-economy of the human groups who lived at Qesem and may mark a threshold to new modes of Palaeolithic human adaptation.


Asunto(s)
Médula Ósea , Huesos/química , Almacenamiento de Alimentos/historia , Animales , Arqueología , Médula Ósea/química , Carnivoría , Culinaria/historia , Diáfisis , Conducta Alimentaria , Herbivoria , Historia Antigua , Humanos , Israel , Piel , Tendones
5.
Neuropathol Appl Neurobiol ; 44(2): 172-184, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28574607

RESUMEN

AIMS: It is important to predict response to treatment with temozolomide (TMZ) in glioblastoma (GBM) patients. Both MGMT protein expression and MGMT promoter methylation status have been reported to predict the response to TMZ. We investigated the prognostic value of quantified MGMT protein levels in tumour cells and the prognostic importance of combining information of MGMT protein level and MGMT promoter methylation status. METHODS: MGMT protein expression was quantified in tumour cells in 171 GBMs from the population-based Region of Southern Denmark (RSD)-cohort using a double immunofluorescence approach. Pyrosequencing was performed in 157 patients. For validation we used GBM-patients from a Nordic Study (NS) investigating the effect of radiotherapy and different TMZ schedules. RESULTS: When divided at the median, patients with low expression of MGMT protein (AF-low) had the best prognosis (HR = 1.5, P = 0.01). Similar results were observed in the subgroup of patients receiving the Stupp regimen (HR = 2.0, P = 0.001). In the NS-cohort a trend towards superior survival (HR = 1.6, P = 0.08) was seen in patients with AF-low. Including MGMT promoter methylation status, we found for both cohorts that patients with methylated MGMT promoter and AF-low had the best outcome; median OS 23.1 and 20.0 months, respectively. CONCLUSION: Our data indicate that MGMT protein expression in tumour cells has an independent prognostic significance. Exclusion of nontumour cells contributed to a more exact analysis of tumour-specific MGMT protein expression. This should be incorporated in future studies evaluating MGMT status before potential integration into clinical practice.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Anciano , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Femenino , Glioblastoma/genética , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Masculino , Persona de Mediana Edad , O(6)-Metilguanina-ADN Metiltransferasa/genética , Pronóstico , Tasa de Supervivencia
6.
Sci Rep ; 6: 34799, 2016 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-27713562

RESUMEN

Gran Dolina is a cavity infilled by at least 25 m of Pleistocene sediments. This sequence contains the TD6 stratigraphic unit, whose records include around 170 hominin bones that have allowed the definition of a new species, Homo antecessor. This fossil accumulation was studied as a single assemblage and interpreted as a succession of several human home bases. We propose a complete stratigraphic context and sedimentological interpretation for TD6, analyzing the relationships between the sedimentary facies, the clasts and archaeo-palaeontological remains. The TD6 unit has been divided into three sub-units and 13 layers. Nine sedimentary facies have been defined. Hominin remains appear related to three different sedimentary facies: debris flow facies, channel facies and floodplain facies. They show three kinds of distribution: first a group of scattered fossils, then a group with layers of fossils in fluvial facies, and third a group with a layer of fossils in mixed fluvial and gravity flow facies. The results of this work suggest that some of these hominin remains accumulated in the cave by geological processes, coming from the adjacent slope above the cave or the cave entry, as the palaeogeography and sedimentary characteristics of these allochthonous facies suggest.


Asunto(s)
Fósiles , Sedimentos Geológicos , Hominidae , Animales , Sedimentos Geológicos/análisis , Humanos , Paleontología/métodos , Tamaño de la Partícula , España
7.
Prev Vet Med ; 127: 56-63, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27094141

RESUMEN

In this study we determined mortality in breeding rabbits on 505 commercial farms in Spain during 2006-2014. We obtained our information by carrying out 3278 visits to 490 doe farms (127 also with males), and 877 visits to farms with males, including 132 visits to 15 artificial insemination (AI) centres. The median size of the farms was 769 does (minimum to maximum: 80-9000 does) and 44 males (minimum to maximum: 10-800 males). AI was used on 85% of the 490 doe farms. Females were serviced at 11 days postpartum on 75% of the farms. The mean Monthly Mortality Risk (MMR%) and 95% Binomial confidence interval (CI) in does were 2.82 (2.71-2.93%), and 1.87 (1.41-2.33%) in bucks, over a population of 2,641,709 females and 90,316 males at risk, in the course of the 9-year study; during the 42-day cycle, MMR% was 3.78 (3.67-3.89%). There were 9547 cohorts of females; 41.5% of the does were pregnant and lactating simultaneously, 28.1% only lactating, 17.4% only pregnant and 13% empty and not lactating. The MMR% of does during the last week of pregnancy was 7.05 (6.63-7.47%) and 4.26 (3.90-4.62%) during the 1st week of lactation. Our diagnoses were based on the macroscopic post-mortem examinations performed by a veterinarian on 2065 female rabbits found dead and 368 moribund-euthanized does. In the total 2433 on-farm necropsies on does and 55 males, we found alterations of the respiratory tract compatible with death in 0.70 (0.64-0.76%) MMR% in does, 0.88 (0.56-1.20%) in bucks; and digestive tract in 0.31 (0.27-0.35%) enteritis-diarrhoea, 0.11 (0.09-0.13%) mucoid enteropathy in does and 0.34 (0.14-0.54%) and 0.07 (0-0.16%) in males, respectively. Other primary causes of death were septicaemia, MMR% 0.23 (0.20-0.26%) in does, and 0.10 (0-0.22%) in males, viral haemorrhagic disease 0.22 (0.19-0.25%) in does, and 0.17 (0.03-0.31%) in bucks, metritis, pyometra, or both, 0.21 (0.19-0.25%), and uterine torsion, 0.20 (0.18-0.22%); 1.2 (1.01-1.39%) in the last week of pregnancy. The median age of 2087/2433 necropsied does was 2 parities (minimum to maximum: 1-34 parities) and the mean 3.9. Some changes in housing, feeding and management, to improve breeding rabbit health, are highlighted.


Asunto(s)
Crianza de Animales Domésticos , Causas de Muerte , Conejos , Animales , Femenino , Masculino , España/epidemiología
8.
Vet Parasitol ; 219: 57-60, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-26921040

RESUMEN

A European goldfinch (Carduelis carduelis), a canary (Serinus canaria), and a lovebird (Agapornis roseicollis) captive-bred at three different private aviaries in Spain were submitted for necropsy with a history of weakness and ruffled feathers, weight loss associated with glossitis, and respiratory disease, respectively. Microscopically, enterocytes in the jejunum and ileum contained colonies of gram- and Stamp-positive, oval to elliptical microorganisms within parasitophorous vacuoles in the apical cytoplasm. Nested PCR using MSP primers that target microsporidian RNA genes produced amplicons of expected size for Encephalitozoon species, and analysis of forward and reverse DNA sequences confirmed the presence of Encephalitozoon hellem in all cases. The main cause of death of all three birds consisted of concurrent infections. However, intestinal encephalitozoonosis may have contributed to exacerbated catabolism. Encephalitozoonosis (or microsporidiosis) has been rarely described in passerine birds.


Asunto(s)
Enfermedades de las Aves/parasitología , Encefalitozoonosis/veterinaria , Agapornis/parasitología , Animales , Enfermedades de las Aves/diagnóstico , Enfermedades de las Aves/patología , Canarios/parasitología , Encephalitozoon/fisiología , Encefalitozoonosis/diagnóstico , Encefalitozoonosis/parasitología , Encefalitozoonosis/patología , Femenino , Pinzones/parasitología , Intestinos/parasitología , Intestinos/patología , Masculino , España
20.
J Anim Sci ; 90(9): 3252-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22585815

RESUMEN

Live BW and BCS data were collected from 2,775 breeding rabbits (644 males and 2,131 females) of 34 genetic types and sorted according to their specialization (maternal, paternal, and others). Data were gathered on 66 visits to 43 commercial farms in Spain between 2009 and 2011. Mean BW was 4.72 kg (range of 2.87 to 8.13 kg, with a median BW of 4.60 kg) and mean BCS was 4.6 (range of 1.0 to 9.0, with a median BCS of 5.0). females had heavier (P < 0.05) BW than males and paternal lines of rabbits had greater (P < 0.05) BW than maternal lines and other breeds/lines not selected for meat production. Between 69.3% and 75.4% of the rabbits were deemed healthy by a veterinarian and, as expected, healthy rabbits were heavier (P < 0.05) than sick rabbits diagnosed with rhinitis, mastitis, sore hocks, and several other diseases. Among purebred, maternal lines of rabbits, Hyplus GD24, UPV A, and UPV V were heavier (P < 0.05) than hyplus GD14 and Hyla HL-D lines, and line UPV R had the greatest (P < 0.05) BW among the purebred, paternal lines. Additionally, A×H, A×V, PS19, and P×A crossbreds had greater (P < 0.05) BW than HE-C×D, HL-C×D, H×V, LP×V, and V×P crossbreds among the maternal lines, whereas HE-SL were the heaviest (P < 0.05) crossbred paternal line of rabbits. Additionally, females received greater (P < 0.05) BCS than males and BCS were greater (P < 0.05) in healthy than sick rabbits. Moreover, maternal lines had smaller (P < 0.05) BCS than either paternal lines or other lines/breeds not selected for meat production. Results also indicated a moderate relationship between BCS and BW (r = 0.32), with a 1-point change in BCS equivalent to an ~ 245-g change in BW. results from this study can be used as baseline figures for breeding rabbits in spain and are essential factors in several decisions concerning housing, feeding, reproduction, health, and welfare of breeding rabbits.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Composición Corporal/fisiología , Peso Corporal/fisiología , Conejos/fisiología , Envejecimiento , Animales , Cruzamiento , Femenino , Masculino , Conejos/genética , Factores Sexuales , España
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