Determinants of the phagocytic signal mediated by the type IIIA Fc gamma receptor, Fc gamma RIIIA: sequence requirements and interaction with protein-tyrosine kinases.

The Fc gamma receptor-associated gamma and zeta subunits contain a conserved cytoplasmic motif, termed the immunoglobulin gene tyrosine activation motif, which contains a pair of YXXL sequences. The tyrosine residues within these YXXL sequences have been shown to be required for transduction of a phagocytic signal. We have previously reported that the gamma subunit of the type IIIA Fc gamma receptor (Fc gamma RIIIA) is approximately 6 times more efficient in mediating phagocytosis than the zeta subunit of Fc gamma RIIIA. By exchanging regions of the cytoplasmic domains of the homologous gamma and zeta chains, we observed that the cytoplasmic area of the gamma chain bearing a pair of the conserved YXXL sequences is important in phagocytic signaling. Further specificity of phagocytic signaling is largely determined by the two internal XX amino acids in the YXXL sequences. In contrast, the flanking amino acids of the YXXL sequences including the seven intervening amino acids between the two YXXL sequences do not significantly affect the phagocytic signal. Furthermore, the protein-tyrosine kinase Syk, but not the related kinase ZAP-70, stimulated Fc gamma RIIIA-mediated phagocytosis. ZAP-70, however, increased phagocytosis when coexpressed with the Src family kinase Fyn. These data demonstrate the importance of the two specific amino acids within the gamma subunit YXXL cytoplasmic sequences in phagocytic signaling and explain the difference in phagocytic efficiency of the gamma and zeta chains. These results indicate the importance of Syk in Fc gamma RIIIA-mediated phagocytosis and demonstrate that ZAP-70 and syk differ in their requirement for a Src-related kinase in signal transduction.

Genetic and redox determinants of nitric oxide cytotoxicity in a Salmonella typhimurium model.

Paradoxically, nitric oxide (NO) has been found to exhibit cytotoxic, antiproliferative, or cytoprotective activity under different conditions. We have utilized Salmonella mutants deficient in antioxidant defenses or peptide transport to gain insights into NO actions. Comparison of three NO donor compounds reveals distinct and independent cellular responses associated with specific redox forms of NO. The peroxynitrite (OONO-) generator 3-morpholinosydnonimine hydrochloride mediates oxygen-dependent Salmonella killing, whereas S-nitrosoglutathione (GSNO) causes oxygen-independent cytostasis, and the NO. donor diethylenetriamine-nitric oxide adduct has no antibacterial activity. GSNO has the greatest activity for stationary cells, a characteristic relevant to latent or intracellular pathogens. Moreover, the cytostatic activity of GSNO may best correlate with antiproliferative or antimicrobial effects of NO, which are unassociated with overt cell injury. dpp mutants defective in active dipeptide transport are resistant to GSNO, implicating heterolytic NO+ transfer rather than homolytic NO. release in the mechanism of cytostasis. This transport system may provide a specific pathway for GSNO-mediated signaling in biological systems. The redox state and associated carrier molecules are critical determinants of NO activity.

Swapping structural determinants of ribonucleases: an energetic analysis of the hinge peptide 16-22.

Bovine seminal ribonuclease (BS-RNase) is a homodimeric enzyme strictly homologous to the pancreatic ribonuclease (RNase A). Native BS-RNase is an equilibrium mixture of two distinct dimers differing in the interchange of the N-terminal segments and in their biological properties. The loop 16-22 plays a fundamental role on the relative stability of the two isomers. Both the primary and tertiary structures of the RNase A differ substantially from those of the seminal ribonuclease in the loop region 16-22. To analyze the possible stable conformations of this loop in both enzymes, structure predictions have been attempted, according to a procedure described by Palmer and Scheraga [Palmer, K. A. & Scheraga, H. A. (1992) J. Comput. Chem. 13, 329-350]. Results compare well with experimental x-ray structures and clarify the structural determinants that are responsible for the swapping of the N-terminal domains and for the peculiar properties of BS-RNase. Minimal modifications of RNase A sequence needed to form a stable swapped dimer are also predicted.

Social determinants and health effects of low and high severity intimate partner violence

PURPOSE: We sought to analyze whether the sociodemographic profile of battered women varies according to the level of severity of intimate partner violence (IPV), and to identify possible associations between IPV and different health problems taking into account the severity of these acts. METHODS: A cross-sectional study of 8,974 women (18-70 years) attending primary healthcare centers in Spain (2006-2007) was performed. A compound index was calculated based on frequency, types (physical, psychological, or both), and duration of IPV. Descriptive and multivariate procedures using logistic regression models were fitted. RESULTS: Women affected by low severity IPV and those affected by high severity IPV were found to have a similar sociodemographic profile. However, divorced women (odds ratio [OR], 8.1; 95% confidence interval [CI], 3.2-20.3), those without tangible support (OR, 6.6; 95% CI, 3.3-13.2), and retired women (OR, 2.7; 95% CI, 1.2-6.0) were more likely to report high severity IPV. Women experiencing high severity IPV were also more likely to suffer from poor health than were those who experienced low severity IPV. CONCLUSIONS: The distribution of low and high severity IPV seems to be influenced by the social characteristics of the women involved and may be an important indicator for estimating health effects. This evidence may contribute to the design of more effective interventions.

A metasynthesis of qualitative studies regarding opinions and perceptions about barriers and determinants of health services’ accessibility in economic migrants

Background: Access to health services is an important health determinant. New research in health equity is required, especially amongst economic migrants from developing countries. Studies conducted on the use of health services by migrant populations highlight existing gaps in understanding which factors affect access to these services from a qualitative perspective. We aim to describe the views of the migrants regarding barriers and determinants of access to health services in the international literature (1997–2011). Methods: A systematic review was conducted for Qualitative research papers (English/Spanish) published in 13 electronic databases. A selection of articles that accomplished the inclusion criteria and a quality evaluation of the studies were carried out. The findings of the selected studies were synthesised by means of metasynthesis using different analysis categories according to Andersen’s conceptual framework of access and use of health services and by incorporating other emergent categories. Results: We located 3,025 titles, 36 studies achieved the inclusion criteria. After quality evaluation, 28 articles were definitively synthesised. 12 studies (46.2%) were carried out in the U.S and 11 studies (42.3%) dealt with primary care services. The participating population varied depending mainly on type of host country. Barriers were described, such as the lack of communication between health services providers and migrants, due to idiomatic difficulties and cultural differences. Other barriers were linked to the economic system, the health service characteristics and the legislation in each country. This situation has consequences for the lack of health control by migrants and their social vulnerability. Conclusions: Economic migrants faced individual and structural barriers to the health services in host countries, especially those with undocumented situation and those experimented idiomatic difficulties. Strategies to improve the structures of health systems and social policies are needed.

Social determinants of self-perceived discrimination in Spain

Objectives: To analyse the association between self-perceived discrimination and social determinants (social class, gender, country of origin) in Spain, and further to describe contextual factors which contribute to self-perceived discrimination. Methods: Cross-sectional design using data from the Spanish National Health Survey (2006). The dependent variable was self-perceived discrimination, and independent and stratifying variables were sociodemographic characteristics (e.g. sex, social class, country of origin, educational level). Logistic regression was used. Results: The prevalence of self-perceived discrimination was 4.2% for men and 6.3% for women. The likelihood of self-perceived discrimination was higher in people who originated from low-income countries: men, odds ratio (OR) 5.59 [95% confidence interval (CI) 4.55–6.87]; women, OR 4.06 (95% CI 3.42–4.83). Women were more likely to report self-perceived discrimination by their partner at home than men [OR 8.35 (95% CI 4.70–14.84)]. The likelihood of self-perceived discrimination when seeking work was higher among people who originated from low-income countries than their Spanish counterparts: men, OR 13.65 (95% CI 9.62–19.35); women, OR 10.64 (95% CI 8.31–13.62). In comparison with Spaniards, male white-collar workers who originated from low-income countries [OR 11.93 (95% CI 8.26–17.23)] and female blue-collar workers who originated from low-income countries (OR 1.6 (95% CI 1.08–2.39)] reported higher levels of self-perceived discrimination. Conclusions: Self-perceived discrimination is distributed unevenly in Spain and interacts with social inequalities. This particularly affects women and immigrants.

Social determinants of sexual satisfaction in Spain considered from the gender perspective

Aims: To describe gender- and social class-related inequalities in sexual satisfaction and analyze their relationship with self-perceived health status. Methods: This population-based, cross-sectional study included 7384 sexually active people aged 16 years and over residing in Spain in 2009 (3951 men and 3433 women). The explanatory variables were gender, age, social class, share in performing domestic tasks, spend time looking after oneself, collaborate economically in supporting the family, caring for children, self-perceived health status, and the desire to increase or decrease frequency of having sexual relations. Bivariate and multivariate logistic regression models were fitted. Results: Among women, sexual satisfaction declines progressively after age 45. Sexual satisfaction is 1.7 times higher among women who look after themselves and who feel good compared with those who do not. The odds of wanting to increase sex is 3.3 times higher for women who are satisfied compared with women who desire a lower frequency of sexual intercourses; and good perceived health was associated with sexual satisfaction. In satisfied men, the corresponding odds is 1.9 times that of men desiring to reduce their frequency of sex. Conclusions: Gender and social class inequalities are found in sexual satisfaction. This is associated with perceived health status, adding evidence in support of the World Health Organization definition of sexual health.

A Contribution to The Study of Global Competition for Talent: the determinants of student mobility and its consequences for the internationalization of the labor market. Bruges European Economic Policy (BEEP) Briefing 27/2013

In a globalized economy the skills of the workforce are a key determinant of the competitiveness of a country. One of the goals of Higher Education is precisely to develop the students’ skills in order to allow them to match the increasing demand for highly qualified workers while it is simultaneously the best period of life to acquire multicultural skills. For this reason, the European Union has fostered student mobility through several programs: the Erasmus program and the Bologna process are the best known among them. Although student mobility is a growing phenomenon, publications and research on the subject remain relatively scarce. This paper aims to contribute to that literature through an empirical analysis which exploits a questionnaire submitted to university alumni and focuses on two research questions: what drives studies abroad and what drives expatriation of graduates. Our empirical analysis first shows that exposure to international experiences before entering tertiary education and family background are the main factors influencing student mobility. A second conclusion is that studying abroad increases the international mobility on the labor market. Both confirm previous studies. Moreover, by making a distinction between participating in the Erasmus program and in other exchange programs or internships abroad, we found that the Erasmus program and the other programs or internships have an equivalent influence on the international mobility on the labor market: they increase by 9 to 12.5 percentage points a student’s chance to be mobile on the international labor market. This result shows the legitimacy of the Erasmus program, but it also reveals the important impact of other forms of experience abroad. It provides support for policy makers to encourage mobility programs, in order to foster integration of the European labor market.

Determinants of Financial Capital Use: Review of theories and implications for rural businesses. Factor Markets Working Paper No. 19, February 2012

This paper presents a review of financial economics literature and offers a comprehensive discussion and systematisation of determinants of financial capital use. In congruence with modern financial literature, it is acknowledged here that real and financial capital decisions are interdependent. While the fundamental role of the (unconstrained) demand for real capital in the demand for finance is acknowledged, the deliverable focuses on three complementary categories of the determinants of financial capital use: i) capital market imperfections; ii) factors mitigating these imperfections or their impacts; and iii) firm- and sector-related factors, which alter the severity of financial constraints and their effects. To address the question of the optimal choice of financial instruments, theories of firm capital structure are reviewed. The deliverable concludes with theory-derived implications for agricultural and non-agricultural rural business’ finance.

Patterns and Determinants of Off-Farm Migration: Transfer frictions and persistency of relative income gaps. Factor Markets Working Papers No. 36, February 2013

The inter-sectoral migration of agricultural labour is a complex but fundamental process of economic development largely affected by the growth of agricultural productivity and the evolution of the agricultural relative income gap. Theory and some recent anecdotal evidence suggest that as an effect of large fixed and sunk costs of out-farm migration, the productivity gap between the agricultural and non-agricultural sectors should behave non-monotonically or following a U-shaped evolution during economic development. Whether or not this relationship holds true across a sample of 38 developing and developed countries and across more than 200 EU regions was empirically tested. Results strongly confirm this relationship, which also emphasises the role played by national agricultural policy.

The Determinants of Country Risk in Eastern European Countries. Evidence from Sovereign Bond Spreads. Bruges European Economic Research (BEER) Papers 8/November 2006

The paper studies country risk in two Central and Eastern European countries - Bulgaria and Poland. The long run relationship between the yield differential (spread) of Eastern European national bonds (denominated in US dollars) over a US Treasury bond on one the hand and the country’s fundamentals as well as an US interest rate on the other hand, is examined. The cointegrated VAR model is used. First, the yield differentials are analyzed on a country by country basis to extract stochastic trends which are common for all bonds in a given country. Thereafter, the risk is disentangled into country and higher level risk. This paper is among the first ones which use time series data to study the evidence from sovereign bond spreads in Eastern Europe.

Determinants to Leave Agriculture and Change Occupational Sector: Evidence from an Enlarged EU. Factor Markets Working Document No. 46, May 2013

The objective of this paper is to explore the determinants to leave agriculture and change occupational sector. We adopt a 3-step multivariate probit where we control for selection bias at two stages in the decisions to work and, at a later stage, exit agriculture. The analysis is based on the European Union Labour Force Survey data expanded with additional regional indicators. The main results suggest that younger individuals are more likely to leave farming activities, although the largest outflows of agricultural labour are mainly associated with the retirement of people. Self-employed and family workers are generally less likely to leave agriculture and those with low levels of educations are found to be significantly constrained in entering the non-farm economy. Moreover, labour market conditions at the regional level do matter for switching occupational sector. Differences in the results among the selected new member states and the EU-15 can be explained by the diverse production structures, suggesting different capacities to release and absorb labour.

The Determinants of Investment in Information and Communication Technologies. Bruges European Economic Research (BEER) Papers 16/March 2010

In this paper we investigate the determinants of ICT investment at the macro level for a panel of ten countries over the period 1992-2005. We argue that, since ICT is a General Purpose Technology, its diffusion can be understood only considering the interaction with institutional and structural factors. The empirical results are in line with this view: facilitating factors such as changes in regulation, human capital and the sectoral composition of the economy are relevant determinants for increasing ICT investment.

Determinants of Farm Labour Use: A Comparison between Ireland and Italy. Factor Markets Working Documents No. 60, August 2013

This paper examines the effect of the decoupling of farm direct payments upon the off-farm labour supply decisions of farmers in both Ireland and Italy, using panel data from the Farm Business Survey (REA) and FADN database covering the period from 2002 to 2009 to model these decisions. Drawing from the conceptual agricultural household model, the authors hypothesise that the decoupling of direct payments led to an increase in off-farm labour activity despite some competing factors. This hypothesis rests largely upon the argument that the effects of changes in relative wages have dominated other factors. At a micro level, the decoupling-induced decline in the farm wage relative to the non-farm wage ought to have provoked a greater incentive for off-farm labour supply. The main known competing argument is that decoupling introduced a new source of non-labour income i.e. a wealth effect. This may in turn have suppressed or eliminated the likelihood of increased off-farm labour supply for some farmers. For the purposes of comparative analysis, the Italian model utilises the data from the REA database instead of the FADN as the latter has a less than satisfactory coverage of labour issues. Both models are developed at a national level. The paper draws from the literature on female labour supply and uses a sample selection corrected ordinary least squares model to examine both the decisions of off-farm work participation and the decisions regarding the amount of time spent working off-farm. The preliminary results indicate that decoupling has not had a significant impact on off-farm labour supply in the case of Ireland but there appears to be a significantly negative relationship in the Italian case. It still remains the case in both countries that the wealth of the farmer is negatively correlated with the likelihood of off-farm employment.

Determinants of Financial Development across the Mediterranean. MEDPRO Technical Report No. 29/February 2013

Casual observation shows that that the financial systems in the southern and eastern Mediterranean are unable (or unwilling) to divert the financial resources that are available to them as funding opportunities to private enterprises. Using a sample of both northern and southern Mediterranean countries for the years 1985 to 2009, this study empirically assesses the reasons underlying such conditions. The results show that strong legal institutions, good democratic governance and adequate implementation of financial reforms can have a substantial positive impact on financial development only when they are present collectively. Moreover, inflation appears to undermine banking development, but less so when the capital account is open. Government debt growth appears to weaken credit growth, which confirms that public debt ‘crowds out’ private debt. Lastly, capital inflows appear to primarily have an income effect, increasing income and thereby national savings, and thus increasing the availability of credit.