Cell line derived xenograft mouse models are a suitable in vivo model for studying tumor budding in colorectal cancer

Tumor budding (TB) is an important prognostic parameter in colorectal cancer (CRC) and associated with metastasis. However, the mechanisms of TB have not been fully elucidated and a major limitation is the absence of in vivo models. Here, we determine the suitability of human cell line derived xenografts (CDX) as models of TB in CRC. Pan-cytokeratin (CK)-stained next-generation Tissue Microarrays (ngTMA) of two CDX models (HT-29, n = 12 and HCT-8, n = 8) and human CRC (n = 27 high-grade and 25 low-grade budding tumors, each) were evaluated for TB. Immunohistochemistry for E-cadherin, β-catenin, Ki-67, ZEB1, and TWIST1 was performed. HT-29 and HCT-8 were predominantly high-grade and no/low-grade TB tumors, respectively. TB counts in the tumor center (intratumoral budding, ITB) were significantly higher in HT-29 CDX tumors compared to human CRC (p = 0.0099). No difference was found in TB counts at the invasion front (peritumoral budding, PTB; p=0.07). ITB and PTB were strongly correlated (r = 0.438 and r = 0.62 in CDX and human CRC, respectively). Immunohistochemistry profiles were comparable in CDX and human CRC tissues. TB in the CDX mouse models is phenotypically similar to human CRCs and highlights comparable protein profiles. The HT-29 CDX could be a suitable model for the in vivo assessment of TB.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

The State-of-the-Art of Collaborative Technologies for Initial Vocational Education: A Systematic Literature Review

Future workplaces require collaboration skills in which members of different work communities use technologies to solve complex problems. Vocational education and training (VET) programs need to meet the challenge to prepare students to be part of a competent workforce. Particularly initial vocational education is under pressure to develop learners’ collaboration skills and abilities. To date, however, no attempt has been made to perform a comprehensive review of the use of computer-supported collaborative learning (CSCL) technologies across different vocational education settings to account for contextual factors of VET. In this systematic review, 26 published studies were analyzed with respect to their demographics, research methodology, use of technology, and measured outcomes. This review illuminates that research on CSCL still leaves the vocational learning context as an under-represented field of study. At the same time, technologies offer a range of new types of learning possibilities for vocational education. As the direct result of that development, vocational education is increasingly taking place in new technology-enhanced learning settings. Education can benefit from the opportunities of CSCL technologies, but on the other hand, such technologies create new challenges for facilitating vocational learning. Therefore, this review also identifies three topic areas specific to vocational learning (collaborative writing-to-learn, simulations and game-like solutions, and tangible objects) and enumerates desirable lines for future research

The crazy-paving pattern: a radiological-pathological correlation

The crazy-paving pattern is a linear pattern superimposed on a background of ground-glass opacity, resembling irregularly shaped paving stones. The crazy-paving pattern is initially described as the pathognomonic sign of alveolar proteinosis. Nowadays this pattern is a common finding on high-resolution CT imaging, and can be seen in a number of acute and chronic diseases. The purpose of this paper is to illustrate different diseases that cause this crazy-paving pattern and to correlate the radiological findings from computed tomography with the histopathological findings

Microphytobenthos production and biomass monitoring on intertidal mudflats using remote sensing

Coastal areas and estuaries are ecosystems with a high economic and ecological value. Microphytobenthos organisms form thin biofilms on intertidal mudflats and are important for stabilizing the sediment and transferring inorganic nutrients to the estuarine foodweb. Knowledge about the microphytobenthos is therefore essential for the management of these areas. As intertidal mudflats are not easily accessible for routine sampling and show high spatial variability, remote sensing techniques are increasingly used for monitoring these areas. Despite the wider use of remote sensing techniques in these systems, the potential of these techniques is still not fully explored. We obtained a variety of hyperspectral and satellite images from the Westerschelde and IJzer Estuary to obtain indices suitable for mapping microphytobenthos biomass. The most widely used marker pigment to quantify algal biomass is chlorophyll a. The microbial mats on intertidal mudflats are generally dominated by diatoms, but blooms of noxious algae such asUlva and cyanobacteria are also frequently observed. Using traditional HPLC-pigment analysis techniques, these different algal groups can readily be distinguished based on differences in their marker pigment composition (fucoxanthine/lutein/zeaxanthine). We will explore the potential for mapping different algal groups on hyperspectral images using these marker pigments. In addition, the data on the biomass and composition of the microphytobenthos will be used for modelling the primary production on the mudflats

Evolution of carbonated lacustrine environment with stromatolites : a paleoecological approach (quarry of Montaigu-le-Blin, Limagne graben, Allier, France)

La carrière de Montaigu-le-Blin, située en Limagne bourbonnaise permet d’analyser en détail la sédimentation lacustre aquitanienne et de reconstituer les environnements de dépôt. Les sédiments marneux et calcaires renferment une faune d’eau douce et une flore particulièrement développées. Les dépôts sédimentaires traduisent des variations périodiques du niveau de la tranche d’eau qui provoquent aussi des variations périodiques des conditions chimiques au sein du lac. Ils sont représentatifs de milieux alternativement anoxiques et oxygénés. Ces variations sont le résultat d’alternances de périodes d’humidité variable, et seraient donc d’origine climatique. Ces alternances ont provoqué des variations périodiques des assemblages floro-fauniques : des thanatocœnoses surviennent durant les périodes anoxiques, alors que le développement majeur des algues encroûtantes responsables de la formation de concrétions algaires, apparaît lors des périodes oxygénées. Ces périodes sont également marquées par une augmentation de l’hydrodynamisme, associée à des apports détritiques du bassin versant. Les stromatolithes présents dans le milieu montrent des morphologies très variées, tributaires des associations de flore et de faune (algues, bactéries, fourreaux de larves de Trichoptères) qui les composent, ainsi que de leur milieu de croissance. Les associations de stromatolithes forment des complexes plurimétriques que l’on propose de situer par rapport à un paléorivage

The secretory small GTPase Rab27B as a marker for breast cancer progression.

In contemporary oncology practice, an urgent need remains to refine the prognostic assessment of breast cancer. It is still difficult to identify patients with early breast cancer who are likely to benefit from adjuvant chemotherapy. Although invasion of cancer cells is the main prognostic denominator in tumor malignancy, our molecular understanding and diagnosis are often inadequate to cope with this activity. Therefore, deciphering molecular pathways of how tumors invade and metastasize may help in the identification of a useful prognostic marker. We recently discovered that the secretory small GTPase Rab27B, a regulator of vesicle exocytosis, delivers proinvasive signals for increased invasiveness, tumor size, and metastasis of various estrogen receptor (ER)-positive breast cancer cell lines, both in vitro and in vivo. In human breast cancer specimens, the presence of Rab27B protein proved to be associated with a low degree of differentiation and the presence of lymph node metastasis in ER-positive breast cancer.publishersversionpublishe

Niche complementarity and facilitation drive positive diversity effects on biomass production in experimental benthic diatom biofilms

Up to now, relatively few diversity-production experiments have been performed using microorganisms. Benthic diatom communities from estuarine intertidal mudflats are especially interesting for this purpose as they are relatively species poor and are thus more easy to simulate in laboratory conditions. We studied the effect of diversity on biomass production during microcosm experiments with diatoms assembled in combinations of up to eight species. Our results demonstrate a highly positive effect of biodiversity on production, with transgressive overyielding occurring in more than half of the combinations. These strong positive diversity effects could largely be attributed to positive complementarity effects (covering both niche complementarity and facilitation), although negative selection effects effects at higher diversities. We found a significant positive relation between functional diversity and the net biodiversity effects, indicating niche complementarity. In addition, we provide one of the first mechanistic evidences for facilitation by which biodiversity can enhance ecosystem functioning. This was demonstrated by the improved growth of Cylindrotheca closterium after addition of spent medium obtained from other diatom species. The stimulated growth of C. closterium was explained by a shift to mixotrophic growth with a down-regulation of the photosynthetic apparatus

The secretory small GTPase Rab27B as a marker for breast cancer progression

In contemporary oncology practice, an urgent need remains to refine the prognostic assessment of breast cancer. It is still difficult to identify patients with early breast cancer who are likely to benefit from adjuvant chemotherapy. Although invasion of cancer cells is the main prognostic denominator in tumor malignancy, our molecular understanding and diagnosis are often inadequate to cope with this activity. Therefore, deciphering molecular pathways of how tumors invade and metastasize may help in the identification of a useful prognostic marker. We recently discovered that the secretory small GTPase Rab27B, a regulator of vesicle exocytosis, delivers proinvasive signals for increased invasiveness, tumor size, and metastasis of various estrogen receptor (ER)-positive breast cancer cell lines, both in vitro and in vivo. In human breast cancer specimens, the presence of Rab27B protein proved to be associated with a low degree of differentiation and the presence of lymph node metastasis in ER-positive breast cancer

Geoheritage, a National Inventory in France

International audienceGood protection measures for geological heritage should begin with an inventory of geosites. In France, for example, a law enacted in 2002 grants formal recognition to the notion of geological heritage. An inventory and evaluation were then established on a region-by-region basis. By April 2007, the French Ministry of Environment launched the inventory programme for the nation’s geological heritage and the data are now being collected at a regional scale. The data are being gathered and homogenised, and then transferred to the French National Museum of Natural History for examination.The ratified site data are stored and available for public use on a website (http://inpn.mnhn.fr) in a similar structure to natural data that are also processed and stored (flora, fauna, ecosystems, habitats). Today, protecting global heritage is understood as a dynamic process. Instead of placing objects beneath a display case, the conservation approach is now a more modern, active effort, which facilitates access for knowledge and researc