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We study phase behaviours of lipid--bilayer vesicles functionalised by ligand--receptor complexes made of synthetic DNA by introducing a modelling framework and a dedicated experimental platform. In particular, we perform Monte Carlo simulations that combine a coarse grained description of the lipid bilayer with state of art analytical models for multivalent ligand--receptor interactions. Using density of state calculations, we derive the partition function in pairs of vesicles and compute the number of ligand--receptor bonds as a function of temperature. Numerical results are compared to microscopy and fluorimetry experiments on Large Unilamellar Vesicles decorated by DNA linkers carrying complementary overhangs. We find that vesicle aggregation is suppressed when the total number of linkers falls below a threshold value. Within the model proposed here, this is due to the higher configurational costs required to form inter--vesicle bridges as compared to intra-vesicle loops, which are in turn related to membrane deformability. Our findings and our numerical/experimental methodologies are applicable to the rational design of liposomes used as functional materials and drug delivery applications, as well as to study inter-membrane interactions in living systems, such as cell adhesion., Comment: The first/last two authors contributed equally; accepted for publication in Soft Matter

Short DNA linkers are increasingly being exploited for driving-specific self-assembly of Brownian objects. DNA-functionalized colloids can assemble into ordered or amorphous materials with tailored morphology. Recently, the same approach has been applied to compliant units, including emulsion droplets and lipid vesicles. The liquid structure of these substrates introduces new degrees of freedom: the tethers can diffuse and rearrange, radically changing the physics of the interactions. Unlike droplets, vesicles are extremely deformable and DNA-mediated adhesion causes significant shape adjustments. We investigate experimentally the thermal response of pairs and networks of DNA-tethered liposomes and observe two intriguing and possibly useful collective properties: negative thermal expansion and tuneable porosity of the liposome networks. A model providing a thorough understanding of this unexpected phenomenon is developed, explaining the emergent properties out of the interplay between the temperature-dependent deformability of the vesicles and the DNA-mediated adhesive forces., SCOPUS: ar.j, info:eu-repo/semantics/published

Introduction: Gender, age, physiology (GAP) system have proven to be an easy tool for predicting disease stages and survival in idiopathic pulmonary fibrosis (IPF) patients. Objective: To validate mortality risk as determined by the GAP system in a real-life multicentre IPF population treated with pirfenidone. Methods: The study included patients who received pirfenidone for at least 6 months. The GAP calculator and the GAP index were determined. The primary outcome was all-cause mortality. The prognostic accuracy of the GAP system was evaluated with respect to calibration and discrimination. Results and Conclusion: Sixty-eight IPF patients were enrolled in the study. The median follow-up was 2.4 years (range 0.1-7.4 years). A total of 22 deaths as first event (32%) and of 10 lung transplantation (15%) were recorded. The cumulative incidence of mortality at 1, 2 and 3 years was 10.4%, 22.4% and 38.4%, respectively. The differences between the predicted and observed mortality were not significant for the GAP index while the observed mortality become comparable to that predicted by the GAP calculator only in the third year of follow-up. The C-index for the GAP index was 0.74 (95% CI 0.57-0.93) while the C-statistic value for the GAP calculator was 0.77 (95% CI 0.59-0.95).

In 1992 P.D. James surprised her affectionate crime fiction reading public by issuing a visionary dystopia: The Children of Men. From a thematic point of view, this science fiction novel focuses precisely on the problem of re-generation, since it deals with an utterly hopeless near future where the humankind has become entirely infertile. The novel opens with the news that the last human being to be born on earth, aged 25, was killed in a pub fight in Buenos Aires. The fact is recorded by the main character, Theo Farrel, a fiftiesh professor of Victorian history, who is writing a depressing diary of his life which, in his intention, is also a report of the world’s last days. “Man is diminished if he lives without knowledge of his past”, Theo writes but “without hope of a future he becomes a beast”. This statement is, in my opinion, the conceptual engine of the whole novel, where P.D. James wonderfully exploits the opportunities of the genre in order to discuss troubling topics. As readers we are haunted by questions on the disputable ways this scientifically advanced society deals with human reproduction and death, or on the dangers of unscrupulous uses of science by some kind of political powers to force their will on human beings. But even though I find the themes of the novel extremely fascinating, my aim in this paper is that of showing how, from a media point of view, P.D. James’s text has been re-generated in its film adaptation by Alfonso Cuarón (2006). I believe that any ‘adaptation’, a word in itself rich in scientific suggestions, can be seen as “a dynamic process of re-constitution on a different level which is essential to life”, to quote the AIA Cultural Studies CfP. In the case here under scrutiny a Mexican director has literally re-generated an English novel by re-constituting on screen its geo/gender politics, as I hope to demonstrate through a close comparison between the novel and the film.