264 research outputs found
Retinal glycoprotein enrichment by concanavalin a enabled identification of novel membrane autoantigen synaptotagmin-1 in equine recurrent uveitis.
Complete knowledge of autoantigen spectra is crucial for understanding pathomechanisms of autoimmune diseases like equine recurrent uveitis (ERU), a spontaneous model for human autoimmune uveitis. While several ERU autoantigens were identified previously, no membrane protein was found so far. As there is a great overlap between glycoproteins and membrane proteins, the aim of this study was to test whether pre-enrichment of retinal glycoproteins by ConA affinity is an effective tool to detect autoantigen candidates among membrane proteins. In 1D Western blots, the glycoprotein preparation allowed detection of IgG reactions to low abundant proteins in sera of ERU patients. Synaptotagmin-1, a Ca2+-sensing protein in synaptic vesicles, was identified as autoantigen candidate from the pre-enriched glycoprotein fraction by mass spectrometry and was validated as a highly prevalent autoantigen by enzyme-linked immunosorbent assay. Analysis of Syt1 expression in retinas of ERU cases showed a downregulation in the majority of ERU affected retinas to 24%. Results pointed to a dysregulation of retinal neurotransmitter release in ERU. Identification of synaptotagmin-1, the first cell membrane associated autoantigen in this spontaneous autoimmune disease, demonstrated that examination of tissue fractions can lead to the discovery of previously undetected novel autoantigens. Further experiments will address its role in ERU pathology
Thick disks and halos of spiral galaxies M 81, NGC 55 and NGC 300
By using images from the HST/WFPC2/ACS archive, we have analyzed the spatial
distribution of the AGB and RGB stars along the galactocentric radius of nearby
spiral galaxies M~81, NGC 300 and NGC 55. Using color-magnitude diagrams and
stellar luminosity functions, we gauge the stellar contents of the surroundings
of three galaxies. The red giant population (RGB) identified at large
galactocentric radii yields a distance of Mpc for M~81,
Mpc for NGC 55, and Mpc for NGC 300, and a mean
stellar metallicity of 0.65, 1.25, and 0.87. We find that there are
two number density gradients of RGB stars along the radius, which correspond to
the thick disk and halo components of the galaxies. We confirm the presence of
metallicity gradient of evolved stars at these galaxies, based on the
systematic changes of the color distribution of red giant stars. These results
imply that thick disk might be a general feature of the spiral galaxies, and
endorse a further investigation of the outer stellar edges of nearby spirals,
which is critical in constraining the origin and evolution of galaxies.Comment: 17 pages, 2 tables, 13 figures, accepted to A&
Convergence versus Divergence: Testing Varieties of Capitalism Perspective on the Globalization of Business Practices
This paper analyses links between intra-organizational adaptation and institutional variation across countries. Using the varieties of capitalism viewpoint, we examine strategic options open to multinational firms operating simultaneously in liberal market economies and coordinated market economies. A holistic perspective is achieved by implementing an original ‘index of institutional impact.’ Data are drawn from a survey of the subsidiaries of German firms in the UK in 2007. The results suggest that pressure towards accepting local practices for multinational firms varies across the dimensions in which firms resolve coordination problems, inciting speedy convergence in some, but allowing for maintaining distinctive practices in other
Genome-Wide Identification of Molecular Pathways and Biomarkers in Response to Arsenic Exposure in Zebrafish Liver
10.1371/journal.pone.0068737PLoS ONE87-POLN
High-Performance Work Systems and Organizational Performance in Emerging Economies: Evidence from MNEs in Turkey
This study examines the association between the usage of high-performance work systems (HPWS) by subsidiaries of multinational enterprises (MNEs) in Turkey and employee and subsidiary level outcomes. The study is based on a survey of 148 MNE subsidiaries operating in Turkey. The results show that the usage of HPWS has a significant positive impact on employee effectiveness. However, their impact on employee skills and development, and organizational financial performance are far less clear. Our findings highlight the extent to which HWPS need to be adapted to take account of context-specific institutional realities. © 2014 Springer-Verlag Berlin Heidelberg
T cell immunoengineering with advanced biomaterials
Recent advances in biomaterials design offer the potential to actively control immune cell activation and behaviour. Many human diseases, such as infections, cancer, and autoimmune disorders, are partly mediated by inappropriate or insufficient activation of the immune system. T cells play a central role in the host immune response to these diseases, and so constitute a promising cell type for manipulation. In vivo, T cells are stimulated by antigen presenting cells (APC), therefore to design immunoengineering biomaterials that control T cell behaviour, artificial interfaces that mimic the natural APC-T cell interaction are required. This review draws together research in the design and fabrication of such biomaterial interfaces, and highlights efforts to elucidate key parameters in T cell activation, such as substrate mechanical properties and spatial organization of receptors, illustrating how they can be manipulated by bioengineering approaches to alter T cell function
Palladium–mediated organofluorine chemistry
Producción CientíficaThe substitution of fluorine for hydrogen in a molecule may result in profound changes in its properties and behaviour. Fluorine does not introduce special steric constraints since the F atom has a small size. However, the changes in bond polarity and the possibility of forming hydrogen bonds with other hydrogen donor fragments in the same or other molecules, may change the solubility and physical properties of the fluorinated compound when compared to the non-fluorinated one. Fluorine forms strong bonds to other elements and this ensures a good chemical stability. Altogether, fluorinated compounds are very attractive in materials chemistry and in medicinal chemistry, where many biologically active molecules and pharmaceuticals do contain fluorine in their structure and this has been shown to be essential for their activityJunta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA302U13)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA256U13
Attrition and bias in the MRC cognitive function and ageing study: an epidemiological investigation
BACKGROUND: Any hypothesis in longitudinal studies may be affected by attrition and poor response rates. The MRC Cognitive Function and Ageing study (MRC CFAS) is a population based longitudinal study in five centres with identical methodology in England and Wales each recruiting approximately 2,500 individuals. This paper aims to identify potential biases in the two-year follow-up interviews. METHODS: Initial non-response: Those not in the baseline interviews were compared in terms of mortality to those who were in the baseline interviews at the time of the second wave interviews (1993–1996). Longitudinal attrition: Logistic regression analysis was used to examine baseline differences between individuals who took part in the two-year longitudinal wave compared with those who did not. RESULTS: Initial non-response: Individuals who moved away after sampling but before baseline interview were 1.8 times more likely to die by two years (95% Confidence interval(CI) 1.3–2.4) compared to respondents, after adjusting for age. The refusers had a slightly higher, but similar mortality pattern to responders (Odds ratio 1.2, 95%CI 1.1–1.4). Longitudinal attrition: Predictors for drop out due to death were being older, male, having impaired activities of daily living, poor self-perceived health, poor cognitive ability and smoking. Similarly individuals who refused were more likely to have poor cognitive ability, but had less years of full-time education and were more often living in their own home though less likely to be living alone. There was a higher refusal rate in the rural centres. Individuals who moved away or were uncontactable were more likely to be single, smokers, demented or depressed and were less likely to have moved if in warden-controlled accommodation at baseline. CONCLUSIONS: Longitudinal estimation of factors mentioned above could be biased, particularly cognitive ability and estimates of movements from own home to residential homes. However, these differences could also affect other investigations, particularly the estimates of incidence and longitudinal effects of health and psychiatric diseases, where the factors shown here to be associated with attrition are risk factors for the diseases. All longitudinal studies should investigate attrition and this may help with aspects of design and with the analysis of specific hypotheses
The Cornella Health Interview Survey Follow-Up (CHIS.FU) Study: design, methods, and response rate
BACKGROUND: The aim of this report is to describe the main characteristics of the design, including response rates, of the Cornella Health Interview Survey Follow-up Study. METHODS: The original cohort consisted of 2,500 subjects (1,263 women and 1,237 men) interviewed as part of the 1994 Cornella Health Interview Study. A record linkage to update the address and vital status of the cohort members was carried out using, first a deterministic method, and secondly a probabilistic one, based on each subject's first name and surnames. Subsequently, we attempted to locate the cohort members to conduct the phone follow-up interviews. A pilot study was carried out to test the overall feasibility and to modify some procedures before the field work began. RESULTS: After record linkage, 2,468 (98.7%) subjects were successfully traced. Of these, 91 (3.6%) were deceased, 259 (10.3%) had moved to other towns, and 50 (2.0%) had neither renewed their last municipal census documents nor declared having moved. After using different strategies to track and to retain cohort members, we traced 92% of the CHIS participants. From them, 1,605 subjects answered the follow-up questionnaire. CONCLUSION: The computerized record linkage maximized the success of the follow-up that was carried out 7 years after the baseline interview. The pilot study was useful to increase the efficiency in tracing and interviewing the respondents
Participation in formal learning activities of older Europeans in poor and good health
Little attention has been given to the involvement in formal learning activities (FLA) in the older population when considering different health statuses. The aim of this study is to explore the extent to which possible predictors (derived from previous research as well as a conceptual model) of FLA differ for older people in poor and good health. Data are used from SHARE 2010/2011 for the 50+ populations in 16 European countries. Poor health is defined as self-report of having two or more chronic diseases assessed by a medical doctor, i.e. multimorbidity. Possible predictors of learning activities represent individual characteristics: functional limitations, demography (age, gender, marital status and household size), human capital (achieved level of education), employment, income and participation in other social activities. To assess the predictors of FLA, logistic regression models are used and average marginal estimates are compared across groups. In addition to multimorbidity, labour market activity is used as a grouping variable. The average participation of individuals in the group with multimorbidity was nearly 50 % lower than that in the group in good health (6.5 vs. 13.3 %). Regardless of multimorbidity, human capital proved to be significant predictors of FLA, especially in those active on the labour market. However, the associations were weaker in the multimorbidity group. Also, significant associations were observed of other types of social activities, in particular cultural and leisure activity and volunteering, with FLA. This study suggests that similar factors are predictors of FLA in older people with and without multimorbidity
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