Importancia de la embolización preoperatoria en el tratamiento del quiste óseo aneurismático: Presentación de un caso clínico

Se describe el tratamiento de un quiste óseo aneurismático localizado en el raquis dorsal, en un niño de 8 años de edad. El quiste óseo aneurismático es una lesión benigna y a menudo extremadamente vascular. En la columna puede causar extensa destrucción ósea y compromiso de las estructuras neurales. Se demuestra el valor de la embolización preoperatoria reduciendo la vascularización y permitiendo su extirpación quirúrgica total.I n this report, th e managemen t o f a n aneurysma l bon e cyst i n th e thoraci c spin e o f an 8 year s ol d bo y is described . Aneurysma l bon e is a histologicall y benig n lesio n tha t is ofte n extremel y vascular . I n th e spine , it ca n caus e extensiv e bon e destructio n an d compress neura l structures. Th e valu e o f preoperativ e embo - lizatio n t o reduc e vascularity , allowin g tota l excisio n is demonstrated

Digital synthesis of microcalcifications on digital mammograms

We propose a model to simulate clustered microcalcifications on digital mammograms. The simulation model is based on the gray-level, size and number of microcalcifications per cluster. All the parameters describing the individual microcalcifications and clusters were randomly sampled within a wide range of values, the exception being the center of the cluster; this was interactively positioned to ensure the location of all the microcalcifications inside the breast. Subsequently, a database of clustered microcalcifications was created. These clusters of microcalcifications from this database were tested from indistinguishability from real ones. Two radiologists and one physicist were asked to indicate wether the microcalcifications were either real or simulated. Results ( χ 2 test) indicate that there was not statistical and significant difference between real and simulated clustered microcalcifications

The conservation status of the world’s reptiles

Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved