Inhibition of PTP1B disrupts cell-cell adhesion and induces anoikis in breast epithelial cells.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesProtein tyrosine phosphatase 1B (PTP1B) is a well-known inhibitor of insulin signaling pathways and inhibitors against PTP1B are being developed as promising drug candidates for treatment of obesity. PTP1B has also been linked to breast cancer both as a tumor suppressor and as an oncogene. Furthermore, PTP1B has been shown to be a regulator of cell adhesion and migration in normal and cancer cells. In this study, we analyzed the PTP1B expression in normal breast tissue, primary breast cells and the breast epithelial cell line D492. In normal breast tissue and primary breast cells, PTP1B is widely expressed in both epithelial and stromal cells, with highest expression in myoepithelial cells and fibroblasts. PTP1B is widely expressed in branching structures generated by D492 when cultured in 3D reconstituted basement membrane (3D rBM). Inhibition of PTP1B in D492 and another mammary epithelial cell line HMLE resulted in reduced cell proliferation and induction of anoikis. These changes were seen when cells were cultured both in monolayer and in 3D rBM. PTP1B inhibition affected cell attachment, expression of cell adhesion proteins and actin polymerization. Moreover, epithelial to mesenchymal transition (EMT) sensitized cells to PTP1B inhibition. A mesenchymal sublines of D492 and HMLE (D492M and HMLEmes) were more sensitive to PTP1B inhibition than D492 and HMLE. Reversion of D492M to an epithelial state using miR-200c-141 restored resistance to detachment induced by PTP1B inhibition. In conclusion, we have shown that PTP1B is widely expressed in the human breast gland with highest expression in myoepithelial cells and fibroblasts. Inhibition of PTP1B in D492 and HMLE affects cell-cell adhesion and induces anoikis-like effects. Finally, cells with an EMT phenotype are more sensitive to PTP1B inhibitors making PTP1B a potential candidate for further studies as a target for drug development in cancer involving the EMT phenotype.Landspitali University Hospital Science Fund University of Iceland Research Fund Icelandic Science and Technology Policy Council Research Fund Icelandic Science and Technology Policy - Grant of Excellence Gongum sama

Social justice, access and quality of healthcare in an age of austerity: Users’ perspective from rural Iceland

Publisher's version (útgefin grein)Iceland is sparsely populated but social justice and equity has been emphasised within healthcare. The aim of the study is to examine healthcare services in Fjallabyggð, in rural northern Iceland, from users’ perspective and evaluate social justice, access and quality of healthcare in an age of austerity. Mixed-method approach with transformative design was used. First, data were collected with questionnaires (response rate of 53% [N=732] in 2009 and 30% [N=415] in 2012), and analysed statistically, followed by 10 interviews with healthcare users (2009 and 2014). The results were integrated and interpreted within Bronfenbrenner’s Ecological Model. There was significantly less satisfaction with accessibility and variety of healthcare services in 2012 after services downsizing. Solid primary healthcare, good local elderly care, some freedom in healthcare choice and reliable emergency services were considered fundamental for life in a rural area. Equal access to healthcare is part of a fundamental human right. In times of economic downturn, people in rural areas, who are already vulnerable, may become even more vulnerable and disadvantaged, seriously threatening social justice and equity. With severe cutbacks in vitally important healthcare services people may eventually choose to self-migrate.Road Administration Research FundPeer reviewe

Heilbrigðisþjónusta Fjallabyggðar: Viðhorf íbúa í kjölfar mikilla samfélagsbreytinga

The aim of this paper is to present a study on attitudes of the population in Fjallabyggð towards access to healthcare service and its diversity and quality, in an age of austerity, which the restructuring after the economic collapse of 2008 demanded, and the tunnel in Héðinsfjörður made possible. We used a mixed method with a transformational design. First, data were collected by questionnaires (response rate of 53% in 2009 and 30% in 2012), followed by ten interviews (2009 and 2014). The results were integrated and interpreted within the ecological model of Bronfenbrenner relating to the interactions between the individual and the environment. Findings show significantly less satisfaction with the availability and diversity of healthcare service in 2012, after the merger and downsizing. Solid primary healthcare, good local elderly care, some freedom in healthcare choice and reliable emergency services were considered fundamental for life in a rural area. The results indicate that improved transportation infrastructure contributed positively to the development of healthcare service and enhanced equality and human rights. The financial cutbacks to health institutes, had however, a negative impact on attitudes.Markmið greinarinnar er að kynna niðurstöður rannsóknar á viðhorfum íbúa Fjallabyggðar til aðgengis að heilbrigðisþjónustu, fjölbreytileika hennar og gæða, í kjölfar niðurskurðar og hagræðingar sem efnahagshrun ársins 2008 krafðist og Héðinsfjarðargöngin gerðu mögulega. Notuð var blönduð aðferð með umbreytingarsniði. Fyrst var gögnum safnað með spurningalistum (svarhlutfall 53% árið 2009 og 30% árið 2012), sem fylgt var eftir með tíu viðtölum (2009 og 2014). Niðurstöðurnar voru samþættar og túlkaðar innan vistfræðilíkans Bronfenbrenner sem snýr að gagnkvæmum áhrifum einstaklings og umhverfis. Marktækt minni ánægja var með aðgengi og fjölbreytileika heilbrigðisþjónustunnar árið 2012 eftir sameiningu og niðurskurð í heilbrigðisþjónustunni. Grundvallaratriði fyrir líf á dreifbýlu svæði töldu íbúar vera góða heilsugæslu, góða umönnun aldraðra innan sveitafélagsins, eitthvert frelsi í vali á heilbrigðisþjónustu og áreiðanlega þjónustu í neyðartilvikum. Niðurstöðurnar gefa vísbendingar um að bættar samgöngur hafi átt þátt í jákvæðri þróun í heilbrigðisþjónustu Fjallabyggðar og aukið jöfnuð og mannréttindi íbúanna en að niðurskurður ríkisins til heilbrigðismála hafi haft neikvæð áhrif á viðhorf þeirra.Peer reviewe

Sensitive detection of Aβ protofibrils by proximity ligation - relevance for Alzheimer's disease

<p>Abstract</p> <p>Background</p> <p>Protein aggregation plays important roles in several neurodegenerative disorders. For instance, insoluble aggregates of phosphorylated tau and of Aβ peptides are cornerstones in the pathology of Alzheimer's disease. Soluble protein aggregates are therefore potential diagnostic and prognostic biomarkers for their cognate disorders. Detection of the aggregated species requires sensitive tools that efficiently discriminate them from monomers of the same proteins. Here we have established a proximity ligation assay (PLA) for specific and sensitive detection of Aβ protofibrils via simultaneous recognition of three identical determinants present in the aggregates. PLA is a versatile technology in which the requirement for multiple target recognitions is combined with the ability to translate signals from detected target molecules to amplifiable DNA strands, providing very high specificity and sensitivity.</p> <p>Results</p> <p>For specific detection of Aβ protofibrils we have used a monoclonal antibody, mAb158, selective for Aβ protofibrils in a modified PLA, where the same monoclonal antibody was used for the three classes of affinity reagents required in the assay. These reagents were used for detection of soluble Aβ aggregates in solid-phase reactions, allowing detection of just 0.1 pg/ml Aβ protofibrils, and with a dynamic range greater than six orders of magnitude. Compared to a sandwich ELISA setup of the same antibody the PLA increases the sensitivity of the Aβ protofibril detection by up to 25-fold. The assay was used to measure soluble Aβ aggregates in brain homogenates from mice transgenic for a human allele predisposing to Aβ aggregation.</p> <p>Conclusions</p> <p>The proximity ligation assay is a versatile analytical technology for proteins, which can provide highly sensitive and specific detection of Aβ aggregates - and by implication other protein aggregates of relevance in Alzheimer's disease and other neurodegenerative disorders.</p

Translation and cross-cultural adaptation of the European Health Literacy Survey Questionnaire, HLS-EU-Q16: The Icelandic version

BACKGROUND: Health literacy (HL) is defined as the knowledge and competences of people to meet the complex demands of health in modern society. It is an important factor in ensuring positive health outcomes, yet Iceland is one of many countries with limited knowledge of HL and no valid HL measurement. The aim of this study was to translate the European Health Literacy Survey Questionnaire- short version (HLS-EU-Q16) into Icelandic, adapt the version, explore its psychometric properties and establish preliminary norms. METHODS: The HLS-EU-Q16 translation model included three steps: 1) translation-back-translation of HLS-EU-Q16 including specialists' review (n = 6); 2) cognitive interviewing of lay people (n = 17); and 3) psychometric analysis with survey participants. The HLS-EU-Q16 includes 16 items, with scores ranges from zero (low/no HL) to 16 (high HL). Statistics included were descriptive, internal consistency measured by Cronbach's α, exploratory factor analysis, and multivariate linear regression. RESULTS: After the translation and cognitive interviewing, 11 of the HLS-EU-Q16 items were reworded to adapt the instrument to Icelandic culture while maintaining their conceptual objectives. Survey participants were 251. Internal consistency of the translated and adapted instrument was α = .88. Four factors with eigenvalues > 1.0 explained 62.6% of variance. Principal component analysis with Oblimin rotation presented four latent constructs, "Processing and Using Information from the Doctor" (4 items, α = .77), "Processing and Using Information from the Family and Media" (4 items, α = .85), "Processing Information in Connection to Healthy Lifestyle" (5 items, α = .76), and "Finding Information about Health Problems/Illnesses" (3 items, α = .73). Lower self-rated health was an independent predictor of lower HL (β = -.484, p = .008). Preliminary norms for HL ranged from five to 16 (M 13.7, SD ± 2.6) with 72.5% with sufficient HL (score 13-16), 22% with problematic HL (score 9-12) and 5.5% with inadequate HL (score 0-8). CONCLUSIONS: The Icelandic version of HLS-EU-Q16 is psychometrically sound, with reasonably clear factor structure, and comparable to the original model. This opens possibilities to study HL in Iceland and compare the results internationally. The translation model introduced might be helpful for other countries where information on HL is missing based on lack of validated tools.Háskólinn á Akureyri (IS) research fundPeer Reviewe

Homogeneous and digital proximity ligation assays for the detection of Clostridium difficile toxins A and B

Background: The proximity ligation assay (PLA) detects proteins via their interaction with pairs of proximity probes, which are antibodies coupled to noncomplementary DNA oligonucleotides. The binding of both proximity probes to their epitopes on the target protein brings the oligonucleotides together, allowing them to be bridged by a third oligonucleotide with complementarity to the other two. This enables their ligation and the detection of the resulting amplicon by real-time quantitative PCR (qPCR), which acts as a surrogate marker for the protein of interest. Hence PLA has potential as a clinically relevant diagnostic tool for the detection of pathogens where nucleic acid based tests are inconclusive proof of infection. Methods: We prepared monoclonal and polyclonal proximity probes targeting Clostridium difficile toxins A (TcdA) and B (TcdB) and used hydrolysis probe-based qPCR and digital PCR (dPCR) assays to detect antibody/antigen interactions. Results: The performance of the PLA assays was antibody-dependent but both TcdA and TcdB assays were more sensitive than comparable ELISAs in either single- or dualplex formats. Both PLAs could be performed using single monoclonal antibodies coupled to different oligonucleotides. Finally, we used dPCR to demonstrate its potential for accurate and reliable quantification of TcdA. Conclusions: PLA with either qPCR or dPCR readout have potential as new diagnostic applications for the detection of pathogens where nucleic acid based tests do not indicate viability or expression of toxins. Importantly, since it is not always necessary to use two different antibodies, the pool of potential antibodies useful for PLA diagnostic assays is usefully enhanced

Multiplex Cytological Profiling Assay to Measure Diverse Cellular States

Computational methods for image-based profiling are under active development, but their success hinges on assays that can capture a wide range of phenotypes. We have developed a multiplex cytological profiling assay that “paints the cell” with as many fluorescent markers as possible without compromising our ability to extract rich, quantitative profiles in high throughput. The assay detects seven major cellular components. In a pilot screen of bioactive compounds, the assay detected a range of cellular phenotypes and it clustered compounds with similar annotated protein targets or chemical structure based on cytological profiles. The results demonstrate that the assay captures subtle patterns in the combination of morphological labels, thereby detecting the effects of chemical compounds even though their targets are not stained directly. This image-based assay provides an unbiased approach to characterize compound- and disease-associated cell states to support future probe discovery

Self-rated health and socio-economic status among older adults in Northern Iceland

Publisher's version (útgefin grein)Little is known about self-rated health (SRH) of older people living in more remote and Arctic areas. Iceland is a high-income country with one of the lowest rates of income inequality in the world, which may influence SRH. The research aim was to study factors affecting SRH, in such a population living in Northern Iceland. Stratified random sample according to the place of residency, age and gender was used and data collected via face-to-face interviews. Inclusion criteria included community-dwelling adults ≥65 years of age. Response rate was 57.9% (N = 175), average age 74.2 (sd 6.3) years, range 65–92 years and 57% were men. The average number of diagnosed diseases was 1.5 (sd 1.3) and prescribed medications 3.0 (sd 1.7). SRH ranged from 5 (excellent) to 1 (bad), with an average of 3.26 (sd 1.0) and no difference between the place of residency. Lower SRH was independently explained by depressed mood (OR = 0.88, 95% CI = 0.80–0.96), higher body mass index (OR = 0.93, 95% CI = 0.87–0.99), number of prescribed medications (OR = 0.88, 95% CI = 0.78–1.00) and perception of inadequate income (OR = 0.45, 95% CI = 0.21–0.98). The results highlight the importance of physical and mental health promotion for general health and for ageing in place and significance of economic factors as predictors of SRH.This work was supported by the Háskólinn á Akureyri [R-1803]; Icelandic Regional Development Institute (Byggðastofnun) [102022].Peer Reviewe

Interferon regulatory factor 5 (IRF5) gene variants are associated with multiple sclerosis in three distinct populations

Background: IRF5 is a transcription factor involved both in the type I interferon and the toll-like receptor signalling pathways. Previously, IRF5 has been found to be associated with systemic lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Here we investigated whether polymorphisms in the IRF5 gene would be associated with yet another disease with features of autoimmunity, multiple sclerosis (MS). Methods: We genotyped nine single nucleotide polymorphisms and one insertion-deletion polymorphism in the IRF5 gene in a collection of 2337 patients with MS and 2813 controls from three populations: two case-control cohorts from Spain and Sweden, and a set of MS trio families from Finland. Results: Two single nucleotide polymorphism (SNPs) (rs4728142, rs3807306), and a 5 bp insertion-deletion polymorphism located in the promoter and first intron of the IRF5 gene, showed association signals with values of p<0.001 when the data from all cohorts were combined. The predisposing alleles were present on the same common haplotype in all populations. Using electrophoretic mobility shift assays we observed allele specific differences in protein binding for the SNP rs4728142 and the 5 bp indel, and by a proximity ligation assay we demonstrated increased binding of the transcription factor SP1 to the risk allele of the 5 bp indel. Conclusion: These findings add IRF5 to the short list of genes shown to be associated with MS in more than one population. Our study adds to the evidence that there might be genes or pathways that are common in multiple autoimmune diseases, and that the type I interferon system is likely to be involved in the development of these diseases.Peer Reviewe

Metadata management for high content screening in OMERO

High content screening (HCS) experiments create a classic data management challenge—multiple, large sets of heterogeneous structured and unstructured data, that must be integrated and linked to produce a set of “final” results. These different data include images, reagents, protocols, analytic output, and phenotypes, all of which must be stored, linked and made accessible for users, scientists, collaborators and where appropriate the wider community. The OME Consortium has built several open source tools for managing, linking and sharing these different types of data. The OME Data Model is a metadata specification that supports the image data and metadata recorded in HCS experiments. Bio-Formats is a Java library that reads recorded image data and metadata and includes support for several HCS screening systems. OMERO is an enterprise data management application that integrates image data, experimental and analytic metadata and makes them accessible for visualization, mining, sharing and downstream analysis. We discuss how Bio-Formats and OMERO handle these different data types, and how they can be used to integrate, link and share HCS experiments in facilities and public data repositories. OME specifications and software are open source and are available at https://www.openmicroscopy.org