Do nutritional supplements reduce iron-deficiency anemia in children? Evidence from Ecuador

A micronutrient deficiency during infancy impairs growth, increases the risk of mortality, and can have long term effects on cognitive development. We evaluate a nationwide public policy that administered "sprinkles" to reduce iron-deficiency anemia in children 6 to 59 months of age in Ecuador, a country that has persistent problems with iron-deficiencies among children. We exploit the exogenous age eligibility rule of the program to identify its causal effect, and address non-compliance issues with a Fuzzy RD design and IV models. Our IV estimates suggest that the program reduces Hb levels in children with low Hb but increases Hb levels in children with higher Hb levels. On average, these heterogeneous effects cancel out and both RD and IV estimates yield insignificant effects

The effect of peripheral blood lymphocyte stimulation on zeta chain expression and IL-2 production in Hodgkin's disease

It has been reported that peripheral blood T cells and NK cells express reduced levels of the T-cell receptor signal-transducing zeta chain in Hodgkin's disease (HD). The zeta chain has emerged as a key subunit of the T-cell antigen receptor, which plays a central role in the signal-transducing events leading to T and NK-cell activation. We were interested in determining whether the low zeta chain expression in HD could be corrected by anti-CD3, anti-CD3-rIL-2 ex vivo stimulation. Zeta chain expression was analysed by dual immunofluorescence on permeabilized cells before and after 72 hours of culture. The IL-2 concentration in the culture supernatants was measured by ELISA. Zeta chain was significantly reduced on unstimulated CD4+, CD8+ and CD56+ cells from patients in active disease compared with normal subjects. In patients in complete remission, the values were normal except for CD8+ cells, on which zeta expression remained significantly reduced. Stimulation with anti-CD3 did not change zeta expression. Co-stimulation with rIL-2 increased but did not normalize the proportions of CD4+/zeta+, CD8+/zeta+and CD56+/zeta+cells and IL-2 production in active disease. Stimulation of cells from patients in clinical remission with anti-CD3+rIL-2 increased the proportion of CD8+zeta+cells and normalized IL-2 production levels. Considering the pivotal role of CD3-zeta in immune response, our data suggest that successful immunotherapy approaches in active HD should consider inclusion of other potent cytokines, as well as genetically engineered tumour vaccines. © 2001 Cancer Research Campaign www.bjcancer.co

Desigualtat salarial persistent, inestabilitat salarial i ocupació temporal a Espanya

La desigualtat salarial dels treballadors a temps complet es va reduir durant la segona meitat dels noranta a Espanya. Un treball troba que aquesta reducció es deu a una caiguda de la inestabilitat dels salaris. Com que l'ocupació temporal també es va reduir, s'estudia l'efecte que el tipus de contracte laboral té sobre l'estructura de la desigualtat i es troba que els treballadors temporals pateixen més inestabilitat salarial, el que suggereix que la caiguda en la contractació temporal ajuda a explicar la davallada en la inestabilitat salarial observada.La desigualdad salarial de los trabajadores a tiempo completo se redujo durante la segunda mitad de los noventa en España. Un trabajo relaciona esta reducción con un descenso de la inestabilidad de los salarios. Dado que la ocupación temporal también se redujo, se estudia el efecto que el tipo de contrato laboral tiene sobre la estructura de la desigualdad, y se encuentra que los trabajadores temporales sufren más inestabilidad salarial, lo que sugiere que el descenso en la contratación temporal ayuda a explicar la disminución en la inestabilidad salarial observada.Cross-sectional earnings inequality of male full-time employees falls over the second half of the nineties in Spain. A study finds that such decline was determined by a decrease in earnings instability and an increase in long term inequality. Given the marked decline in temporary employment over the sample period, we also examine the effect of the type of contract on earnings variance components, and find that workers with fixed-term contract face on average more instability than workers with permanent contract. This evidence suggests that the decline in temporary employment is responsible for the decreasing earnings instability

Inequality aversion and risk attitudes

Using self reported measures of life satisfaction and risk attitudes, we empirically test whether there is a relationship between individuals inequality and risk aversion. The empirical analysis uses the German SOEP household panel for the years 1997 to 2007 to conclude that the negative effect of inequality measured by the sample gini coefficient by year and federal state is larger for those individuals who report to be less willing to take risks. Nevertheless, the empirical results suggest that even though inequality and risk aversion are related, they are not the same thing. The paper shows that the relationship between risk attitudes and inequality aversion survives the inclusion of individual characteristics (i.e. income, education, and gender) that may be correlated with both risk attitudes and inequality aversion

Finding the "Dark Matter'' in Human and Yeast Protein Network Prediction and Modelling

Accurate modelling of biological systems requires a deeper and more complete knowledge about the molecular components and their functional associations than we currently have. Traditionally, new knowledge on protein associations generated by experiments has played a central role in systems modelling, in contrast to generally less trusted bio-computational predictions. However, we will not achieve realistic modelling of complex molecular systems if the current experimental designs lead to biased screenings of real protein networks and leave large, functionally important areas poorly characterised. To assess the likelihood of this, we have built comprehensive network models of the yeast and human proteomes by using a meta-statistical integration of diverse computationally predicted protein association datasets. We have compared these predicted networks against combined experimental datasets from seven biological resources at different level of statistical significance. These eukaryotic predicted networks resemble all the topological and noise features of the experimentally inferred networks in both species, and we also show that this observation is not due to random behaviour. In addition, the topology of the predicted networks contains information on true protein associations, beyond the constitutive first order binary predictions. We also observe that most of the reliable predicted protein associations are experimentally uncharacterised in our models, constituting the hidden or "dark matter'' of networks by analogy to astronomical systems. Some of this dark matter shows enrichment of particular functions and contains key functional elements of protein networks, such as hubs associated with important functional areas like the regulation of Ras protein signal transduction in human cells. Thus, characterising this large and functionally important dark matter, elusive to established experimental designs, may be crucial for modelling biological systems. In any case, these predictions provide a valuable guide to these experimentally elusive regions

Not all university degrees yield the same return : private and social returns to higher education for males in Spain

In this paper we use micro data from the Spanish Family Expenditure Survey for 1990 to estimate, for the first time, the private and social rates of return of different university degrees in Spain. We compute internal rates of return and include investment on higher education financed by the public purse to estimate social rates of return. Our main finding is that, as presumed, there is large heterogeneity in rates of return amongst different universit

Recent trends in Spanish income distribution : a robust picture of falling income inequality

Income distribution in Spain has experienced a substantial improvement towards equalisation during the second half of the seventies and the eighties; a period during which most OECD countries experienced the opposite trend. In spite of the many recent papers on the Spanish income distribution, the period covered by those stops in 1990. The aim of this paper is to extent the analysis to 1996 employing the same methodology and the same data set (ECPF). Our results not only corroborate the (decreasing inequality) trend found by others during the second half of the eighties, but also suggest that this trend extends over the first half of the nineties. We also show that our main conclusions are robust to changes in the equivalence scale, to changes in the definition of income and to potential data contamination. Finally, we analyse some of the causes which may be driving the overall picture of income inequality using two decomposition techniques. From this analyses three variables emerge as the major responsible factors for the observed improvement in the income distribution: education, household composition and socioeconomic situation of the household head

Capital humano y desigualdad en España : 1985-1996

En el período 1985-1996 la desigualdad de la renta en España se redujo de forma notable, en claro contraste con lo sucedido en otros países avanzados. En este trabajo se profundiza en el impacto que sobre esta reducción en la desigualdad ha ejercido la redistribución del stock de capital humano, uno de los factores que aparecen como más relevantes para explicar tanto la distribución de la renta como sus modificaciones. Las conclusiones obtenidas sugieren que aproximadamente un tercio de la reducción en la desigualdad que se ha producido entre los dos años extremos contemplados (1985 frente a 1996) se debe al comportamiento del capital humano. Otros factores tales como el tamaño de la familia o la participación de ambos cónyuges en el mercado de trabajo, han actuado en el mismo sentido. Finalmente, un elevado porcentaje de mejora en la distribución permanece por explicar y deberá ser objeto de investigaciones futuras

Desigualdad de rentas y desigualdad de oportunidad en España

Este trabajo proporciona una medición empírica de la desigualdad de renta del trabajo atribuible a la desigualdad de oportunidad entre la población ocupada de España. Esta medición se basa en estimar una ecuación de rentas del trabajo por mínimos cuadrados ordinarios y por variables instrumentales con el fin de controlar por el posible sesgo de endogeneidad de la variable de educación. Los resultados permiten seleccionar el método de los mínimos cuadrados ordinarios para estimar las ecuaciones de rentas del trabajo para cinco cohortes de edad. Así, se mide la magnitud de la desigualdad de oportunidad en España, sus principales determinantes y su evolución a lo largo del ciclo de vida. Asimismo se emplean índices de desigualdad para calcular la reducción de la desigualdad de renta del trabajo que se obtendría si se cumpliera la igualdad de oportunidad, y para evaluar cuales son las circunstancias que más impactarían en esta reducción

Immunoliposome-mediated drug delivery to Plasmodium-infected and non-infected red blood cells as a dual therapeutic/prophylactic antimalarial stragegy

One of the most important factors behind resistance evolution in malaria is the failure to deliver sufficiently high amounts of drugs to early stages of Plasmodium-infected red blood cells (pRBCs). Despite having been considered for decades as a promising approach, the delivery of antimalarials encapsulated in immunoliposomes targeted to pRBCs has not progressed towards clinical applications, whereas in vitro assays rarely reach drug efficacy improvements above 10-fold. Here we show that encapsulation efficiencies reaching N96% are achieved for the weak basic drugs chloroquine (CQ) and primaquine using the pH gradient loading method in liposomes containing neutral saturated phospholipids. Targeting antibodies are best conjugated through their primary amino groups, adjusting chemical crosslinker concentration to retain significant antigen recognition. Antigens from non-parasitized RBCs have also been considered as targets for the delivery to the cell of drugs not affecting the erythrocytic metabolism. Using this strategy, we have achieved unprecedented complete nanocarrier targeting to early intraerythrocytic stages of the malaria parasite for which there is a lack of specific extracellular molecular tags. Immunoliposomes studded with monoclonal antibodies raised against the erythrocyte surface protein glycophorin A were capable of targeting 100% RBCs and pRBCs at the low concentration of 0.5 μM total lipid in the culture, with N95% of added liposomes retained on cell surfaces. When exposed for only 15 min to Plasmodium falciparum in vitro cultures of early stages, free CQ had no significant effect on the viability of the parasite up to 200 nM, whereas immunoliposomal 50 nM CQ completely arrested its growth. In vivo assays in mice showed that immunoliposomes cleared the pathogen below detectable levels at a CQ dose of 0.5 mg/kg, whereas free CQ administered at 1.75 mg/kgwas, atmost, 40-fold less efficient. Our data suggest that this significant improvement is in part due to a prophylactic effect of CQ found by the pathogen in its host cell right at the very moment of invasion