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Failures of small internal diameter vascular grafts have been caused by the lack of a stable endothelial lining to form on their artificial surfaces. Polymer surfaces can be optimized by means of proper treatment to allow a homogeneous and uniform coverage in artificial prosthesis applications. Several solutions were studied to improve cell attachment and growth on artificial materials. In the present study, polyethyleneterephthalate (PET) surfaces were treated by plasma processes with oxygen and ammonia and also in the presence of a gas mixture to verify the effect of functional groups grafting onto the endothelial cell growth. Related surface chemical modifications were investigated by X-ray photoelectron spectroscopy (XPS). Then using cytotoxicity and cytocompatibility tests, the biocompatibility of the modified PET surfaces was assessed by studying the behavior of human umbilical vein endothelial cells (HUVEC). The results showed that plasma-treated PET samples have no toxic effect on HUVEC. The cytocompatibility tests revealed an increase in cell growth with incubation time and the presence of well-spread and flattened cells (SEM analyses). Thus it is reported that plasma treatments can improve PET biocompatibility to HUVEC.

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Measuring population changes and trends is essential to identify threatened species, and is requested by several environmental regulations (e.g. European Habitat Directive). However, obtaining this information for small and cryptic animals is challenging, and requires complex, broad-scale monitoring schemes. How should we allocate the limited resources available for monitoring, to maximize the probability of detecting declines? The analysis of simulated data can help to identify the performance of monitoring scenarios across species with different features. We simulated data of populations with a wide range of abundance, detection probability and rate of decline, and tested under which circumstances open-population N-mixture models can successfully detect the decline of populations. We tested multiple monitoring strategies, to identify the ones having the highest probability of detecting declines. If 30 sites are surveyed, strong declines (≥30%) can be successfully spotted for nearly all the simulated species, except the species with lowest abundance and detection probability. Weaker declines are successfully identified only in species that are easy to detect and have high abundance. Increasing the number of sites quickly increases model power, but hundreds of sites would require monitoring to measure trends of the least detectable species. For most of species, performance of monitoring was improved by: surveying many sites with a few replicates per site; surveying many small sites instead of a few large sites; combining data from sites monitored for multiple species. Our findings show that one single monitoring approach cannot be appropriate for all the species, and that surveying efforts should be modulated across them, according to their detection probabilities and abundances. We provide quantitative values on how the number of surveys and the number of sites to be surveyed can be assigned to different species, and emphasize the need of planning to maximize the performance of monitoring.

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Aim To infer the phylogenetic relationships and biogeography of Hydromantes, with special emphasis on the European taxa. In particular, we aimed to test: (1) the monophyly of the European species and current views on their interrelationships; and (2) previously proposed timings of the separation of European and American Hydromantes, and of biogeographically important events within Europe.Location California and the Western Mediterranean Basin, specifically southeast France, Italy, and the island of Sardinia.Methods Partial sequences of mitochondrial genes (cytochrome b and 12S rRNA) were obtained from 45 specimens of Hydromantes, including all European extant species and subspecies, and two species from California. In addition, a fragment of the mitochondrial 16S rRNA gene was amplified for 16 specimens. Data sets were aligned using ClustalX, and well-supported phylogenetic trees were produced using maximum-likelihood, Bayesian and maximum-parsimony methods. Estimates of divergence times were obtained with the program r8s, the molecular clock being calibrated using the opening of the Strait of Gibraltar, the final event in the Messinian Salinity Crisis of 5.3 Ma.Results Separation between the American and European clades occurred approximately 13.5 Ma, most probably before or after westward dispersal across the Bering Land Bridge. In Europe, divergence started in the late Miocene, when Hydromantes (A.) genei separated from other members of the genus 9 Ma and colonized south-west Sardinia. Movement between the European mainland and Sardinia, by a member of the subgenus Speleomantes, occurred in the Messinian Salinity Crisis, after the Mediterranean Basin desiccated almost completely 5.96 Ma. Subsequent widespread aridification fragmented the geographical ranges of Hydromantes, which live in cool and humid conditions, resulting in the origin of the six species in the subgenus Speleomantes. In contrast, a second period of diversification, in continental Europe 2-1.3 Ma, was probably caused by very cold interludes during the climatic oscillations that characterized the Pleistocene. Main conclusionsThe molecular clock used here indicates that the separation of Californian and European Hydromantes occurred more recently than previously believed, and the same is true of some subsequent phylogenetic divergences within Europe. Estimated dates for these divergence events are consistent with known geophysical and climatic events that could have caused or facilitated them.

The Italian endemic genus Salamandrina has been historically regarded as monotypic but, recently, studies based on both mitochondrial and nuclear markers have indicated the existence of two distinct species of spectacled salamanders: Salamandrina perspicillata, in central and northern Italy, and Salamandrina terdigitata, in southern Italy. We analyzed nucleotide variation at mitochondrial and nuclear genes [cytochrome b, 12S and 16S rRNA, recombination activating gene (RAG 1)] in 223 individuals from 56 locations, aiming to investigate their genetic structure and recent evolutionary histories. Phylogenetic and phylogeographical analyses revealed the existence of three and two genetically distinct groups of populations in northern and southern salamander, respectively. Historical demographic analyses led to the inference of range expansion for both species in the late Pleistocene. During the last glacial stage, each salamander survived in a single refugium, namely the southern in Calabria and the northern in central Italy. At the end of this period, both lineages expanded northward and established secondary contact. Spatial distribution of RAG 1 haplotype variation revealed two differentiated population groups corresponding to the major mitochondrial (mt)DNA clades. Nuclear pattern of introgressive hybridization was more extensive than the highly limited introgression of mtDNA markers. From a conservation standpoint, southern Latium and Calabria proved to be the major genetic diversity reservoirs, thus deserving particular conservation effort

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