Direct Thy-1/alphaVbeta3 integrin interaction mediates neuron to astrocyte communication.

Thy-1 is an abundant neuronal glycoprotein of poorly defined function. We recently provided evidence indicating that Thy-1 clusters a beta3-containing integrin in astrocytes to induce tyrosine phosphorylation, RhoA activation and the formation of focal adhesions and stress fibers. To date, the alpha subunit partner of beta3 integrin in DI TNC1 astrocytes is unknown. Similarly, the ability of neuronal, membrane-bound Thy-1 to trigger astrocyte signaling via integrin engagement remains speculation. Here, evidence that alphav forms an alphavbeta3 heterodimer in DI TNC1 astrocytes was obtained. In neuron-astrocyte association assays, the presence of either anti-alphav or anti-beta3 integrin antibodies reduced cell-cell interaction demonstrating the requirement of both integrin subunits for this association. Moreover, anti-Thy-1 antibodies blocked stimulation of astrocytes by neurons but not the binding of these two cell types. Thus, neuron-astrocyte association involved binding between molecular components in addition to the Thy-1-integrin; however, the signaling events leading to focal adhesion formation in astrocytes depended exclusively on the latter interaction. Additionally, wild-type (RLD) but not mutated (RLE) Thy-1 was shown to directly interact with alphavbeta3 integrin by Surface Plasmon Resonance analysis. This interaction was promoted by divalent cations and was species-independent. Together, these results demonstrate that the alphavbeta3 integrin heterodimer interacts directly with Thy-1 present on neuronal cells to stimulate astrocytes.

Psychometrics of the Dyadic Coping Inventory in three language groups

This article introduces the Dyadic Coping Inventory (DCI; Bodenmann, 2008) and aims (1) to investigate the reliability and aspects of the validity of the Italian and French versions of the DCI, and (2) to replicate its factor structure and reliabilities using a new Swiss German sample. Based on 216 German-, 378 Italian-, and 198 French-speaking participants, the factor structure of the original German inventory was able to be replicated by using principal components analysis in all three groups after excluding two items in the Italian and French versions. The latter were shown to be as reliable as the German version with the exception of the low reliabilities of negative dyadic coping in the French group. Confirmatory factor analyses provided additional support for delegated dyadic coping and evaluation of dyadic coping. Intercorrelations among scales were similar across all three languages groups with a few exceptions. Previous findings could be replicated in all three groups, showing that aspects of dyadic coping were more strongly related to marital quality than to dyadic communication. The use of the dyadic coping scales in the actor-partner interdependence model, the common fate model, and the mutual influence model is discussed.

Cis interactions of immunoreceptors with MHC and non-MHC ligands

The conventional wisdom is that cell-surface receptors interact with ligands expressed on other cells to mediate cell-to-cell communication (trans interactions). Unexpectedly, it has recently been found that two classes of receptors specific for MHC class I molecules not only interact with MHC class I molecules expressed on opposing cells, but also with those on the same cell. These cis interactions are a feature of immunoreceptors that inhibit, rather than activate, cellular functions. Here, we review situations in which cis interactions have been observed, the characteristics of receptors that bind in trans and cis, and the biological roles of cis recognition.

Patients who attend a private practice vs a university outpatient clinic: how do they differ?

Although interpersonal continuity is commonly assumed to be essential for care, some patients prefer to attend a university outpatient clinic where physicians change regularly and interpersonal continuity of care is not ensured. The aim of this exploratory study was to evaluate the differences between patients attending a university outpatient clinic and patients frequenting a private practice, explore their patterns of care-seeking and their understanding of continued care. We conducted a cross-sectional study of patients attending the university medical outpatient clinic (OC) in Lausanne, Switzerland and ten randomly selected private general practices (PP). Eligible patients were >30 years, Swiss nationals or long term residents, with one or more chronic conditions and attending the same practice for >3 years. They were asked to complete a questionnaire on sociodemographic data, use of medical resources and reasons for choosing and remaining at the same practice. Semi-structured interviews were conducted with a randomly selected subset of 26 patients to further explore their preferences. 329 patient questionnaires were completed, 219 by PP and 110 by OC patients. OC patients tended to be of lower socioeconomic status than PP patients. The main reason for choosing a PP were personal recommendation, while a higher percentage of patients chose the OC because they could obtain a first appointment quickly. A higher percentage of PP patients accorded importance to physician communication skills and trust, whereas a higher percentage of OC patients favoured investigation facilities. Qualitative data suggested that although OC and PP patients reported different reasons for consulting, their expectations on the medical and relationship level were similar. Our study suggests that the two groups of patients belong to different social backgrounds, have different patterns of care-seeking and attach importance to different aspects of care continuity. However, patients' expectations and perceptions of the physician-patient relationship are similar.