Abundance and recruitment data for Undaria pinnatifida in Brest harbour, France: Model versus field results.

The data presented in this article are related to the research article entitled "A modelling approach to explore the critical environmental parameters influencing the growth and establishment of the invasive seaweed Undaria pinnatifida in Europe" [1]. This article describes raw simulation data output from a novel individual-based model of the invasive kelp species Undaria pinnatifida. It also includes field data of monthly abundance and recruitment values for a population of invasive U. pinnatifida (in Brest harbour, France) that were used to validate the model. The raw model output and field data are made publicly available in order to enable critical analysis of the model predictions and to inform future modelling efforts of the study species.

[Introduction and establishment processes of marine species: a study case with the Japanese brown kelp Undaria pinnatifida]. / Processus et dynamique d'installation des espèces introduites en milieu marin: une illustration avec l'algue brune asiatique Undaria pinnatifida.

The number of biological introductions has increased since the 1970's and is now considered as the second major cause of the biodiversity erosion, after fragmentation or disappearance of habitat. Beyond the threat they represent for the ecosystem equilibrium, introduced species are interesting models to study fundamental issues in ecology and evolution like the processes of dispersal and adaptation to novel environments. In this context, species introduced over a large geographic range and spectrum of habitats provide an excellent opportunity for comparing the mechanisms that promote introduction and settlement between different environments. In this paper, based on a case study, the worldwide introduction of the brown alga Undaria pinnatifida, and on the use of molecular tools, we aim at examining several processes promoting or occurring during biological introductions. Our results showed that i) multiple processes can account for the success of the pandemic introduction of this alga, highlighting the necessity to study introduced species in relation with the ecosystem they invaded, ii) the recurrence of introductions is a critical component in the dynamics of settlement and iii) human activities can play a major role not only during the primary introduction but also for the sustainable settlement of introduced species in natural environments by providing reservoir of migrants. Taken together, these results demonstrate that the complexity of mechanisms occurring in biological invasion require spatial but also long-term analysis.

Differential shuffling of native genetic diversity across introduced regions in a brown alga: aquaculture vs. maritime traffic effects.

Worldwide marine invaders, such as the brown alga Undaria pinnatifida, offer challenging models for unraveling the apparent paradox of sustainable settlement of exotic species over a large spectrum of environments. Two intergenic noncoding mitochondrial loci were found to be highly informative at the within-species level. Twenty-five haplotypes were found over the whole dataset (333 base pairs, 524 individuals, and 24 populations). The native range showed striking population genetic structure stemming from low diversity within and high differentiation among populations, a pattern not observed in the introduced range of this seaweed. Contrary to classical expectations of founding effects associated with accidental introduction of exotic species, most of the introduced populations showed high genetic diversity. At the regional scale, genetic diversity and sequence divergence showed contrasting patterns in the two main areas of introduction (Europe and Australasia), suggesting different processes of introduction in the two regions. Gene genealogy analyses point to aquaculture as a major vector of introduction and spread in Europe but implicate maritime traffic in promoting recurrent migration events from the native range to Australasia. The multiplicity of processes and genetic signatures associated with the successful invasion confirms that multiple facets of global change, e.g., aquaculture practices, alteration of habitats, and increased traffic, act in synergy at the worldwide level, facilitating successful pandemic introductions.

The entheses: histology, pathology, and pathophysiology.

The entheses are the sites of attachment of ligaments, tendons, and joint capsules to bone. Their ubiquitous distribution throughout the body explains the considerable clinical and radiological polymorphism of entheseal diseases. In addition to aging and mechanical factors, many disorders related to a vast array of pathophysiological mechanisms can produce entheseal disease. The spondyloarthropathies provide the most striking examples of entheseal involvement in inflammatory joint disease. Over the last few decades, major advances have shed light on the biochemical composition of the entheses, their histological features, their mechanical role, and their evaluation by ultrasonography and magnetic resonance imaging. These new insights have generated valuable hypotheses about the pathogenesis of spondyloarthropathies.

Colic metastases of alveolar soft-part sarcoma: a case report and review of the literature.

Alveolar soft-part sarcoma is a rare soft tissue malignant tumor that commonly arises in skeletal muscles or musculofascial planes in children and young adults. Metastases of lung, brain, and bone are often present at the time of diagnosis or appear late in the course of disease. We present the first case, to our knowledge, of colic metastases in a 43-year-old woman who had a leg primary tumor more than 15 years ago and multiple lung and brain metastases. The treatment of these two caecal metastases, revealed by an anemia, consisted in laparoscopic right colectomy.

Aberrant axon neurofilaments in schwannomas associated with phacomatoses.

Neurofibromas and schwannomas express S100 protein, while axon filaments are not commonly found in schwannomas. Histopathological distinction between neurofibromas and schwannomas is usually easy, except for some variants. To assess the reliability of immunohistochemistry results for the differential diagnosis of the latter, 46 neural tumors of the skin were studied: 31 schwannomas [12 schwannomatosis, 7 neurofibromatosis type 2 (NF2)-associated, 12 solitary] and 15 plexiform neurofibromas associated with neurofibromatosis type 1. All tumors were subjected to immunohistochemical-labeling studies with antibodies to S100 protein and axon-specific neurofilament proteins. All tumors were positive with anti-S100 protein antibody. Schwannomas were strongly and diffusely positive while neurofibromas displayed more varied and limited S100 protein reactivity. Axon filaments were detected in 15 of 15 plexiform neurofibromas and 7 of 19 schwannomas associated with NF2/schwannomatosis. None of the 12 solitary schwannomas reacted with anti-axon neurofilament antibodies. Aberrant axons were observed in the schwannomas associated with NF2/schwannomatosis but not in the solitary schwannomas. Therefore, when there are multiple neural tumors, immunohistochemical visualization of axons may be misleading if it is not related to the clinical context and the standard histological features.

Magnetic resonance imaging for the diagnosis of stress fractures in a horse.

In humans, magnetic resonance (MR) imaging is the method of choice for the diagnosis of stress fractures. In this paper, bilateral stress fracture of the lateral condyle of the third metacarpal bone in a French trotter is described. Results of the radiographic, MR imaging, and histologic examinations are presented, with a focus on the MR signal abnormalities found. Based on this patient, the potential use of MR imaging for the diagnosis of stress fractures in horses is discussed.