Trasplante celular y terapia regenerativa con células madre

Uno de los campos de la medicina que más expectativas ha levantado en los últimos años es la terapia celular con células madre. El aislamiento de células embrionarias humanas, la aparente e inesperada potencialidad de las células madre adultas y el desarrollo de la terapia génica nos llevar a imaginar un futuro esperanzador para un importante número de enfermedades actualmente incurables. A lo largo de las siguientes páginas vamos a tratar de dibujar el panorama de la investigación con células madre, describiendo los principales logros en este campo así como algunas de las preguntas pendientes de responder. A pesar de las grandes expectativas, es fundamental que mantengamos un espíritu crítico y realista a la hora de analizar los avances científicos en esta área

Does education engender cultural values that matter for economic growth?

Empirical research has shown that cultural values matter for economic growth and has specifically identified the achievement motivation as an aspect of culture that engenders economic growth. If specific cultural values engender economic growth, how then can societies promote them? This paper attempts to answer this question using the 2005 wave of the World Values Survey data for 43 countries. We test the contention that education significantly impacts the relative importance an individual places on economic achievement vis-à-vis traditional social norms. Results suggest that individuals with higher education levels attach higher importance to values related to autonomy and economic achievement as compared to conformity to traditional social norms. The results have an important implication for efforts to promote economic development; institutions and specifically public policy on education could be used to encourage people to adopt values that are considered important for economic development.Cultural Values, Education, Ordered Probit, Semi-Nonparametric Estimation

What determines workers’ preferences for efficiency over equity wages?

What makes workers consider it fair for wages to be indexed on job performance or efficiency? In this paper we attempt to answer this question using the 2005 wave of the World Values Survey data for 43 countries to investigate what socio-economic characteristics condition employees’ preference for efficiency over equity wages. Our results suggest that employees’ preference for efficiency wages increases with education and globalization while it decreases with unemployment, income inequality and income tax rates. Given that conventional economic theory demonstrates the importance of labour efficiency, which improves when workers are remunerated according to their efficiency, for economic growth; our results suggest that institutions and specifically public policies that promote education, and globalization, along with policies that reduce unemployment, income inequality and income tax rates could be used to promote efficiency-based wages.

Does education engender cultural values that matter for economic growth?

Empirical research has shown that cultural values matter for economic growth and has specifically identified the achievement motivation as an aspect of culture that engenders economic growth. If specific cultural values engender economic growth, how then can societies promote them? This paper attempts to answer this question using the 2005 wave of the World Values Survey data for 43 countries. We test the contention that education significantly impacts the relative importance an individual places on economic achievement vis-à-vis traditional social norms. Results suggest that individuals with higher education levels attach higher importance to values related to autonomy and economic achievement as compared to conformity to traditional social norms. The results have an important implication for efforts to promote economic development; institutions and specifically public policy on education could be used to encourage people to adopt values that are considered important for economic development

Simulation-Based Frequentist Inference with Tractable and Intractable Likelihoods

High-fidelity simulators that connect theoretical models with observations are indispensable tools in many sciences. When coupled with machine learning, a simulator makes it possible to infer the parameters of a theoretical model directly from real and simulated observations without explicit use of the likelihood function. This is of particular interest when the latter is intractable. We introduce a simple modification of the recently proposed likelihood-free frequentist inference (LF2I) approach that has some computational advantages. The utility of our algorithm is illustrated by applying it to three pedagogically interesting examples: the first is from cosmology, the second from high-energy physics and astronomy, both with tractable likelihoods, while the third, with an intractable likelihood, is from epidemiology

What determines workers’ preferences for efficiency over equity wages?

What makes workers consider it fair for wages to be indexed on job performance or efficiency? In this paper we attempt to answer this question using the 2005 wave of the World Values Survey data for 43 countries to investigate what socio-economic characteristics condition employees’ preference for efficiency over equity wages. Our results suggest that employees’ preference for efficiency wages increases with education and globalization while it decreases with unemployment, income inequality and income tax rates. Given that conventional economic theory demonstrates the importance of labour efficiency, which improves when workers are remunerated according to their efficiency, for economic growth; our results suggest that institutions and specifically public policies that promote education, and globalization, along with policies that reduce unemployment, income inequality and income tax rates could be used to promote efficiency-based wages

Stem Cells and Cardiac Disease: Where are We Going?

During the last 10 years we have witnessed the development of a new field in research termed Stem Cell Therapy. Classically, it was considered that cells had a limited division and differentiation ability; however, this dogma was challenged when new exciting results about cell multi/pluripotency were presented to the scientific community. It was found that cells from one adult tissue source were able to originate cells of a very different type. The possibility of transplanting these cells into damaged organs with the aim of substituting sick or dead tissue, triggered many studies to understand the plasticity of the stem cells and their potential in pathological situations. Nowadays, much more is understood about stem cells, although of course, many questions, especially about their mechanism of action, still need to be answered. Their benefit after transplantation has been shown experimentally and even clinically in some cases; however, the degree of stem cell contribution through their own differentiation into the transplanted tissue, has turned out to be generally low, and increasing evidence indicates that a trophic effect must play an important role in such a benefit. A better understanding of the paracrine mechanisms involved could be of great relevance in order to develop new therapies focused on stimulating endogenous cells. On the other hand, more sophisticated methods for cell transplantation combined with bio-engineering techniques have been devised in cardiac disease models. In this review we will try to provide a critical overview of the stem cell studies performed until now and to discuss some of the questions raised about the mechanisms that are involved in their putative reparative effect in cardiovascular diseases, and their origin

The Impact of Heavy Load Carrying on Musculoskeletal Pain and Disability Among Women in Shinyanga Region, Tanzania.

BackgroundHeavy load carrying has been associated with musculoskeletal discomfort (MSD) and disability. However, there is a lack of research investigating this association in resource-constrained settings where heavy load carrying by women is common.ObjectivesWe assessed the impact of heavy load carrying on musculoskeletal pain and disability among women in Shinyanga Region, Tanzania, in an exploratory cross-sectional study.MethodsEligible participants were a convenience sample of women, at least 18 years of age, who passed a study recruitment site carrying a load. We collected information on load-carrying practices, including frequency and time spent carrying water, wood, agricultural products, coal, sand, or rocks, and measured the weight of the load carried at the time. Outcomes included self-reported MSDs, defined as experiencing pain lasting >3 days in the neck, head, back, knees, feet and/or ankles within the last 1 year, and related disability. Using multivariable logistic regression we assessed for associations between load carrying exposures and MSDs and disability.FindingsResults showed a high prevalence of MSDs across the body regions assessed and evidence to suggest a relationship of back pain and related disability with several measures of load-carrying, including duration, frequency, and weight. Multivariable analyses revealed associations of increased load carrying exposures with low back pain (LBP) and related disability, including statistically significant increases in odds of LBP with increasing weight, total duration of load carrying/week and cumulative loads/week.ConclusionsFindings indicate a substantial burden of MSDs and disability in this population of women who carry heavy loads daily. The extent of discomfort and disability increased with increasing exposure to various load-carrying measures, especially for LBP. Larger epidemiologic studies that definitively assess relationships of load carrying with MSDs and disability are warranted