Establishement of plasma membrane politary in mammary epithelial cells correlates with changes in prolactin trafficking and in annexin VI recruitment to membranes

International audienc

Lipidomics of the red cell in diagnosis of human disorders.

International audienceApplications of tandem mass spectrometry in the field of lipid clinical chemistry are considered. Haemato-logical and biochemical advantages are presented favoring the choice of red blood cell membranes as a starting material in a wide variety of biomedical fields. Practical considerations are discussed with respect to methods of sampling, storage, and lipid extraction of red blood cells. The chapter describes the capabilities of a direct infusion of raw lipid extracts in the electro-spray ionization source compared with the more sophisticated method of high-performance liquid chromatography coupled with hybrid tandem mass spectrometry. Both methods have been evaluated and have been shown to be suitable for diagnosis and/or monitoring for a variety of human disorders

When the term “schizophrenia” is enough to modify the way you interact with others: Evidence for a motor synchrony task

IntroductionMost individuals with schizophrenia will be confronted with some forms of stigmatization. In recent years, the term “schizophrenia” has been increasingly contested by clinicians and family members and many of them argue for a change of name. Surprisingly, most of the research has been explored though self-reports but behavioural research is still lacking. The aim of our study was to assess through an experimental design if the term “schizophrenia” was enough to modify social behaviours.MethodsEleven participants from the community were asked to engage in three coordination tasks with a simple dot displayed on a screen and moved by another person. Participants had to synchronize their movements with either a schizophrenia patient, a patient with neuro-emotional integration disorder (NEID) or a healthy subject, situated in different rooms. Each condition was counterbalanced between participants. In reality, the movements of the dot were pre-recorded (five trajectories) and were therefore identical for all three conditions.ResultsMeasuring the error between the displayed and performed trajectories, participants coordinate worse when they though interacting with a schizophrenia or NEID patient in comparison to the “healthy” (F(2.20) = 4.02; P = .034; n2P = 0.29) condition. Post-hoc analysis revealed an even higher difference between “schizophrenia” and “healthy” conditions (P = 0.01).ConclusionOur study is the first to demonstrate that the label “schizophrenia” directly impacts our behaviour, with negative consequences on social interactions. However, our results cannot confirm yet a positive effect induced by changing the name.Disclosure of interestThe authors have not supplied their declaration of competing interest.</jats:sec

Building Up of the Liquid-Ordered Phase Formed by Sphingomyelin and Cholesterol

AbstractThe long-range and molecular orders and dynamics in codispersions of egg sphingomyelin-cholesterol have been investigated by synchrotron x-ray diffraction and electron spin resonance using phosphatidylcholine spin-labeled at several positions on the sn-2 chain. Mixtures containing 0, 17, 33, 41, 50mol% cholesterol exhibited a single phase by x-ray diffraction methods. The temperature dependence of the d-spacing between 20 and 50°C is attenuated with increasing proportions of cholesterol, becoming invariant for cholesterol contents of 41 and 50mol% on completion of the liquid-ordered phase. Electron spin resonance revealed two sites for 17 and 33mol% cholesterol. One site is highly ordered and the other is less ordered than the fluid phase of pure sphingomyelin as shown by the molecular and the intramolecular order parameters reflecting the segmental motions of the probe. The two-sites exchange rate indicates a mean lifetime of the sites of ∼0.1μs during which the lipid displacement is ∼1nm. The short lifetime of the sites probed by ESR and the single phase detected by x-ray diffraction support in this binary mixture, the building up of the Lo phase by a progressive accumulation of randomly distributed sphingomyelin-cholesterol condensed complexes rather than by diffusional exchange between extended domains