Estimating lagoonal biodiversity in Greece: comparison of rapid assessment techniques

An attempt is made to compare the results of different rapid biodiversity assessment techniques at the pan-Mediterranean, sectorial and local levels. A uniform multivariate pattern exists at the pan-Mediterranean and national (sectorial) levels: lagoons can be different when they host only a few species, but as species numbers increase, lagoons become homogenous in composition. Multivariate techniques cannot distinguish anthropogenically-impacted lagoons from those, which are naturally disturbed. In the pan-Mediterranean context it is the higher taxonomic levels, but in the national and local context it is the most abundant macrobenthic groups (polychaetes, molluscs and crustaceans) and meiobenthos which provide patterns closest to that derived from the species level. Taxonomic distinctness indices applied to polychaete and mollusc inventories provide meaningful results at most levels and scales of observation. These indices seem to be robust enough to discriminate anthropogenically impacted from naturally disturbed lagoons.     

Ouabain stimulates endothelin release and expression in human endothelial cells without inhibiting the sodium pump.

Ouabain, a sodium pump (Na+/ K+-ATPase) inhibitor, has been shown to act as a hormone and is possibly involved in the pathogenesis of hypertension. The mechanism by which ouabain may act was investigated using primary cultures of human umbilical artery endothelial cells (HUAECs), which are known to express and release the vasoconstrictive hormone endothelin (ET-1). Five minutes after application, low concentrations of ouabain induced Ca2+ oscillations and stimulated ET-1 release from endothelial cells into the medium. To investigate whether the observed effects were due to inhibition of the sodium pump, the effects of ouabain on the uptake of 86Rb+ by HUAECs were examined. Unexpectedly, ouabain concentrations below 10 nm stimulated 86Rb+ uptake by 15-20%, and in some experiments by 50%, results that are consistent with a stimulation of the pump. Within the concentration range 1-10 nm, ouabain induced a 2.5-fold stimulation (phosphorylation) of mitogen-activated protein kinase (MAP kinase). After incubation of HUAECs with ouabain for 12 h, the glycoside stimulated cell growth by 49 +/- 4%, as measured by cell number, with a maximum response at 5 nm. At similar concentrations, ouabain also increased ET-1 mRNA abundance by 19.5 +/- 3.1%. The results indicate that, by influencing ET-1 expression and release, ouabain may contribute to the regulation of vascular tone. The data also confirm that it is not a global inhibition of the sodium pump that is involved in the mechanism of action of this cardiac glycoside.     

Integrating phenotype ontologies across multiple species

Phenotype ontologies are typically constructed to serve the needs of a particular community, such as annotation of genotype-phenotype associations in mouse or human. Here we demonstrate how these ontologies can be improved through assignment of logical definitions using a core ontology of phenotypic qualities and multiple additional ontologies from the Open Biological Ontologies library. We also show how these logical definitions can be used for data integration when combined with a unified multi-species anatomy ontology.     

Impact of Early Colonizers on In Vitro Subgingival Biofilm Formation

The aim of this study was to investigate the impact of early colonizing species on the structure and the composition of the bacterial community developing in a subgingival 10-species biofilm model system. The model included Streptococcus oralis, Streptococcus anginosus, Actinomycesoris, Fusobacterium nucleatum subsp. nucleatum, Veillonella dispar, Campylobacter rectus, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Based on literature, we considered Streptococcus oralis, Streptococcus anginosus, and Actinomyces oris as early colonizers and examined their role in the biofilms by either a delayed addition to the consortium, or by not inoculating at all the biofilms with these species. We quantitatively evaluated the resulting biofilms by real-time quantitative PCR and further compared the structures using confocal laser scanning microscopy following fluorescence in situ hybridisation. The absence of the early colonizers did not hinder biofilm formation. The biofilms reached the same total counts and developed to normal thickness. However, quantitative shifts in the abundances of individual species were observed. In the absence of streptococci, the overall biofilm structure appeared looser and more dispersed. Moreover, besides a significant increase of P. intermedia and a decrease of P. gingivalis , P. intermedia appeared to form filamented long chains that resembled streptococci. A. oris, although growing to significantly higher abundance in absence of streptococci, did not have a visible impact on the biofilms. Hence, in the absence of the early colonizers, there is a pronounced effect on P. intermedia and P. gingivalis that may cause distinct shifts in the structure of the biofilm. Streptococci possibly facilitate the establishment of P. gingivalis into subgingival biofilms, while in their absence P. intermedia became more dominant and forms elongated chains.     

Structural basis for IL-12 and IL-23 receptor sharing reveals a gateway for shaping actions on T versus NK cells

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Alternative Mode of E-Site tRNA Binding in the Presence of a Downstream mRNA Stem Loop at the Entrance Channel

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Genetic diversity of the brown marmorated stink bug <Emphasis Type="Italic">Halyomorpha halys</Emphasis> in the invaded territories of Europe and its patterns of diffusion in Italy

Halyomorpha halys is an invasive stink bug pest originating from East Asia. In Europe, it was first detected in Switzerland in 2004. It is now present in thirteen countries, and seems to be spreading throughout the continent. In Italy, where it has been recorded since 2012, other than being an urban nuisance, it is causing severe damage in commercial fruit orchards. An integrated approach, using current and previous observational data in space and time and molecular information, was used to identify the genetic diversity of this pest in Europe, its invasion history, and the potential pathways of entry and diffusion. The analysis of 1175 bp of mitochondrial DNA cytochrome c oxidase I and II genes (cox1, cox2) led to the identification of twenty previously unknown haplotypes. The European distribution of H. halys is the result of multiple invasions that are still in progress, and, in some cases, it was possible to identify the specific Asian areas of origin. Moreover, secondary invasions could have occurred among European countries by a bridgehead effect. In Italy, the data were more clearly related to their temporal occurrence, allowing for a clearer reading of the patterns of invasion and dispersion. After having successfully established in localized areas, H. halys further expanded its range by an active dispersion process and/or by jump dispersal events due to passive transport. The multiple introductions from different areas of the native range together with the different patterns of diffusion of H. halys, may hamper the pest management strategies for its containment.