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Ciliates comprise species synthesizing water-diffusible mating type factors or pheromones and species synthesizing insoluble, cell membrane-bound pheromones. Euplotes crassus has traditionally been placed in the latter group. In contrast with this notion, we found that E. crassus is a constitutive pheromone-secreting ciliate, like other Euplotes species. From cell-free filtrate preparations of the E. crassus strain L-2D, we isolated two distinct pheromones, designated as Ec-± and Ec-1, and determined their complete amino acid sequences by combined chemical and genetic approaches. The Ec-± pheromone sequence extends for 56 amino acid residues with six cysteines and shows a molecular mass of 6,183 Da, while the Ec-1 pheromone sequence extends for 45 amino acid residues with 10 cysteines and shows a molecular mass of 4,840 Da. Marked structural differences distinguish the full-length Ec-± and Ec-1 coding sequences, which have been cloned and characterized from the transcriptionally active macronuclear genome. They were taken as clear indication that the Ec-± and Ec-1 pheromones are specified by genes that are not allelic, but likely derived from a duplicated genetic locus of the transcriptionally silent micronuclear genome

Three-dimensional wet-spun microfibrous meshes of a star poly(∈-caprolactone) were developed as potential scaffolds endowed with antimicrobial activity. The in vitro release kinetics of the meshes, under physiological conditions, was initially fast and then a sustained release for more than one month was observed. Cell cultures of a murine pre-osteoblast cell line showed good cell viability and adhesion on the wet-spun star poly(∈-caprolactone) fiber scaffolds. These promising results indicate a potential application of the developed meshes as engineered bone scaffolds with antimicrobial activity.

In the last two decades, large scale axenic cell cultures of the marine species comprising the family Euplotidae have resulted in the isolation of several new classes of terpenoids with unprecedented carbon skeletons including the (i) euplotins, highly strained acetylated sesquiterpene hemiacetals; (ii) raikovenals, built on the bicyclo[3.2.0]heptane ring system; (iii) rarisetenolides and focardins containing an octahydroazulene moiety; and (iv) vannusals, with a unique C30 backbone. Their complex structures have been elucidated through a combination of nuclear magnetic resonance spectroscopy, mass spectrometry, molecular mechanics and quantum chemical calculations. Despite the limited number of biosynthetic experiments having been performed, the large diversity of ciliate terpenoids has facilitated the proposal of biosynthetic pathways whereby they are produced from classical linear precursors. Herein, the similarities and differences emerging from the comparison of the classical chemotaxonomy approach based on secondary metabolites, with species phylogenesis based on genetic descriptors (SSU-rDNA), will be discussed. Results on the interesting ecological and biological properties of ciliate terpenoids are also reported.

New pigments with all unprecedented skeleton, named keronopsamides A-C, were isolated from the marine ciliate Pseudokeronopsis riccii. The structure of the most abundant secondary metabolite, keronopsamide A, was established through extended Nuclear Magnetic Resonance (NMR) analysis and mass spectrometric (MS) data obtained by using electrospray (ESI) and matrix assisted laser desorption (MALDI) ionizations. Structures of the minor analogues (keronopsamide B and C) were inferred from H-1 NMR, chemical correlation, and LC-MS measurements The analysis of NOE dipolar Couplings and quantum chemical calculations, carried out by density functional theory (DFT) oil the preferred rotamers of keronopsamide A, suggested a fully planar structure with amide bond in anti stereochemistry capable to break down the extended conjugation of the whole pi electronic system. Although the presence of a 2-substituted 3,4-dibromo-pyrrole moiety is reminiscent of previously isolated metabolites isolated from a cell extract of Pseudokeronopsis rubra (keronopsins), keronopsamides show a new molecular skeleton formally derived from a peptide-like condensation of a 3-pyrrolepropenoic acid with all unsaturated bromotyramine

The new echocardiographic techniques for the study of physiopathological intramyocardial phenomena include video densitometry (VD), integrated backscatter (IBS), and color Doppler myocardial imaging (CDMI). Being more independent from cardiac load and from rotational and translational heart motion, these new sensible, noninvasive techniques such as CDMI and IBS show a real incremental value in comparison with conventional echocardiography and allow to detect subtle functional and textural abnormalities of intramural myocardium, partially undetectable by conventional two-dimensional Doppler echocardiography. Subclinical thyroid dysfunction (STD), both in its hypo- and hyperthyroidism form, has a relatively high prevalence in general population (9-15% with a lower percentage of adult males), hence it could be very useful to study more deeply heart involvement in these physiopathological conditions and understand the complex relationship between thyroid and heart. The use of these new ultrasonic techniques in subclinical hypothyroidism helps to detect the early simultaneous involvement of both cardiac cycle phases, which causes a decrease of intramyocardial contractility and an impairment of both active and passive phases of diastole. In subclinical hyperthyroidism, these new ultrasonic techniques permitted to discover more complex and different early cardiac abnormalities of both systolic and diastolic phases.

International audience; PTZ (pan-tilt-zoom) camera networks have an important role in surveillance systems. They have the ability to direct the attention to interesting events that occur in the scene. In order to achieve such behavior the cameras in the network use a process known as sensor slaving: one (or more) master camera monitors a wide area and tracks moving targets so as to provide the positional information to one (or more) slave camera. The slave camera foveates at the targets in high resolution. In this paper, we propose a simple method to solve two typical problems that are the basic building blocks to create high level functionality in PTZ camera networks: the computation of the world to image homographies and the computation of camera to camera homographies. The first one is used for computing the image sensor observation model in sequential target tracking, the second one is used for camera slaving. Finally a cooperative tracking approach exploiting the use of both homographies is presented.