[Psychological and cognitive interventions in end-of-life support of patients with amyotrophic lateral sclerosis. A review.] / Prise en charge psychologique et cognitive au cours de l'accompagnement de fin de vie de patients atteints de sclérose latérale amyotrophique. Une revue systématique.

Amyotrophic lateral sclerosis (ALS) is an incurable disease characterized by muscle atrophy leading to complete paralysis. Once diagnosed, the average life expectancy is three to five years. In this context, palliative and end-of-life care are essential, as well as the development of cognitive and/or psychological therapies to improve the quality of life of patients. In this context, we conducted a review of the pertinent literature about psychological and cognitive interventions in end-of-life support for ALS patients. We identified 504 references out of which only four studies met our inclusion criteria. Two studies focused on dignity therapy, one study on the delay between the diagnosis and the start of psychological care in a specialized centre, and one case-report on psychological therapy combined with a computer-assisted communication system. The results of these studies, although very limited, suggest that psychological interventions may improve the management and quality of life of end-of-life ALS patients. Further studies should investigate the impact of psychological support adapted to ALS, using, for example, computer-assisted communication allowing to implement these interventions in a larger number of patients and over the long term.

La sclérose latérale amyotrophique (SLA) est une maladie neurogénérative qui se caractérise notamment par une amyotrophie progressive évoluant jusqu'à la paralysie complète du patient dont l'espérance de vie est, en moyenne, de trois à cinq ans. Les soins palliatifs et le développement de thérapies pour améliorer la qualité de vie des patients sont essentiels. Dans ce cadre, nous avons réalisé une revue de la littérature portant sur les interventions psychologiques et cognitives dans la prise en charge des patients atteins de SLA en fin de vie. Nous avons identifié 504 références dont quatre rapportant des études qui répondaient aux critères d'inclusion. Deux études portaient sur la thérapie de la dignité, une sur la rapidité d'une prise en charge psychologique dans un centre spécialisé et un rapport de cas concernait une prise en charge psychologique combinée à un système de communication assistée par ordinateur. Les résultats de ces quatre études, bien que limités, suggèrent que les interventions psychologiques pourraient améliorer la qualité de vie des patients en fin de vie. De nouvelles recherches devraient être menées pour investiguer l'impact d'une prise en charge psychologique adaptée à la SLA en utilisant, par exemple, une communication assistée afin d'implémenter ces interventions sur un plus grand nombre de patients et sur le long terme.

Detection of secondary structures in 17-mer Ru(II)-labeled single-stranded oligonucleotides from luminescence lifetime studies.

The emission properties of a non intercalating complex, [Ru(TAP)2(dip)]2+ (TAP = 1,4,5,8-tetraazaphenanthrene; dip = 4,7-diphenyl-1,10-phenanthroline), tethered to 17-mer single-stranded oligodeoxyribonucleotides (ODNs) either in the middle or at the 5'-end of the sequence, are determined. The results highlight the fact that the luminescence of this metallic compound is sufficiently sensitive to its microenvironment to probe self-structuration of these short single-stranded ODNs. It is shown that the weighted averaged emission lifetimes (tau(M)) along with the quenching rate constants of luminescence by oxygen reflect particularly well different structures adopted by the different ODNs sequences. The determination of these parameters thus offers an elegant way to examine possible structurations of synthetic single-stranded ODNs that play important roles in biological applications.

Engineering regulable Escherichia coli beta-galactosidases as biosensors for anti-HIV antibody detection in human sera.

The activity of engineered, peptide-displaying enzymes is modulated by binding to specific anti-peptide antibodies. This new concept of a quantitative antibody detection system allows test kits to be set up for fast diagnosis of infectious diseases. To develop a quick and homogeneous assay for the detection of human immunodeficiency virus (HIV) infection, we have explored two acceptor sites of the bacterial Escherichia coli beta-galactosidase for the accommodation of HIV antigenic peptides. Two overlapping epitopes (namely P1 and P2) from the gp41 envelope glycoprotein, contained in different sized peptides, were inserted in the vicinity of the enzyme active site to generate a set of hybrid, enzymatically active beta-galactosidases. Regulable enzymes of different responsiveness to monoclonal antibody binding were generated with both acceptor sites tested. These biosensors were also sensitive to immune sera from HIV-infected patients. Modeling data provide insight into the structural modifications in the vicinity of the active site induced by peptide insertion that strongly affect the responsiveness of the engineered proteins through different parameters of their catalytic properties.

Refolding simulations of an isolated fragment of barnase into a native-like beta hairpin: evidence for compactness and hydrogen bonding as concurrent stabilizing factors.

Experimental evidence and theoretical models both suggest that protein folding is initiated within specific fragments intermittently adopting conformations close to that found in the protein native structure. These folding initiation sites encompassing short portions of the protein are ideally suited for study in isolation by computational methods aimed at peering into the very early events of folding. We have used Molecular Dynamics (MD) technique to investigate the behavior of an isolated protein fragment formed by residues 85 to 102 of barnase that folds into a beta hairpin in the protein native structure. Three independent MD simulations of 1.3 to 1.8 ns starting from unfolded conformations of the peptide portrayed with an all-atom model in water were carried out at gradually decreasing temperature. A detailed analysis of the conformational preferences adopted by this peptide in the course of the simulations is presented. Two of the unfolded peptides conformations fold into a hairpin characterized by native and a larger bulk of nonnative interactions. Both refolding simulations substantiate the close relationship between interstrand compactness and hydrogen bonding network involving backbone atoms. Persistent compactness witnessed by side-chain interactions always occurs concomitantly with the formation of backbone hydrogen bonds. No highly populated conformations generated in a third simulation starting from the remotest unfolded conformer relative to the native structure are observed. However, nonnative long-range and medium-range contacts with the aromatic moiety of Trp94 are spotted, which are in fair agreement with a former nuclear magnetic resonance study of a denaturing solution of an isolated barnase fragment encompassing the beta hairpin. All this lends reason to believe that the 85-102 barnase fragment is a strong initiation site for folding.