Papel de los esfingolipidos en la senalizacion celular

Este trabajo ha recibido financiación del Ministerio de Educación\ud y Ciencia (SAF-2005-00602

Influence of Business Incubators Performance on Entrepreneurial Intentions and Its Antecedents during the Pre-incubation Stage

The pre-incubation phase is critical in the forming of entrepreneur?s intention and however it is almost missing in literature. Using the entrepreneurship models based on the beliefs?attitude?intention relationship, a sample of 167 pre-incubated entrepreneurs within the well-known System of Business Incubators of the Monterrey Institute of Technology and Higher Education was surveyed and its statistical analysis developed with Structural Equation Modelling methodology. Our findings confirm that (1) entrepreneur?s perception concerning the incubator?s performance directly and positively affects the desirability, self-efficacy and the facilitating conditions, (2) the perceived desirability and feasibility in entrepreneurship, as well as the first ones, self-efficacy and facilitating conditions, positively influence the entrepreneurial intentions. Furthermore, contrary to the traditional mind-set that supports risk is a barrier, results suggest that (3) the risk perceived by pre-incubated entrepreneurs positively influences entrepreneurial intentions and the desirability that is attributed to that behaviour. Finally, these results also provide insights for organizational leaders and policymakers into managing business incubators and organising their formative programs. The effectiveness of incubators is clear but it is also important to communicate it properly so that incubated individuals can perceive it

Turning teachers into entrepreneurship role models: development of a measurement scale of useful characteristics

The circumstances under which students consider their teachers of entrepreneurship as role models have not received in-depth exploration in the literature. This paper focuses on determining the main personal, professional and pedagogical characteristics that would turn teachers of entrepreneurship into role models and thereby improve the entrepreneurial intentions of students. A three-step empirical research process combining documentary, qualitative and quantitative methods is developed in order to propose and test a measurement scale of teacher characteristics that is reliable, valid and useful for causal modelling. A total of 26 characteristics are identified and classified into personal, professional and pedagogical categories

Social entrepreneur: same or different from the rest?

ABSTRACT: A social business responds to social problems usually ignored by institutions, mobilizing resources and generating employment. To gain more knowledge about this type of enterprise, the key factors that may influence social entrepreneurship are studied and compared with nonsocial entrepreneurship. This enables advances in the scientific literature and the design of more effective policies that encourage the creation of social enterprises. To achieve this goal, after delimiting the area of study, a sample of 25,631 entrepreneurs in 59 countries was used; 9,792 of these are social entrepreneurs collected by the Global Entrepreneurship Monitor project in 2015 when a special issue focused on this topic. The results show that the majority of the factors that determine the decision to undertake nonsocial entrepreneurship also condition the individual to undertake social entrepreneurship, although the nature of their relationship or the intensity of the influence changes

The Moderating Effect of Countries' Development on the Characterization of the Social Entrepreneur: An Empirical Analysis with GEM Data

The objective of this paper is to analyze the moderating effect that the level of development of countries exerts on the factors that define the behavior of social entrepreneurs, distinguishing the effect produced in innovation-driven economies from that in factor/efficiency-driven economies. Our study contributes to the advancement of one of the most relevant problems detected in social entrepreneurship research: the lack of empirical quantitative studies, mainly due to the lack of harmonized and comparable international data. We perform an empirical multivariable analysis using 2015 Global Entrepreneurship Monitor data related to social entrepreneurship. The results show that both the variables that measure the values and skills to start a business and those related to the environment differentiate social from commercial entrepreneurs. In addition, our findings show how the development of the country plays a decisive moderating role, modifying the effect of the values and skills to be a social entrepreneur, the influence of gender, and even the relevance of entrepreneurs'perception of their environment

Influence of perceived risk on entrepreneurial desirability and feasibility: multidimensional approach for nascent entrepreneurs

ABSTRACT: This study examines the influence of perceived risk on entrepreneurial desirability and feasibility as determining factors in the intention to start a self-owned business. Specifically, a multidimensional approach is taken to examine the different types of risks associated with entrepreneurship: economic, social, time, health and personal risks. The results obtained from a sample of 376 new entrepreneurs in Mexico confirm the fact that the perceived desirability and feasibility have a significant and positive effect on the intentions to start their own company. On one hand, the empirical evidence obtained shows a heterogenic effect of the risk dimensions associated with entrepreneurship on the perceived desirability and feasibility in their behaviour. Therefore, it was found that the economic risk associated with entrepreneurship has a negative effect on the feasibility to start a business, but does not significantly influence the desirability of that behaviour. On the other hand, a significant effect from the risk related to health is not seen on desirability and feasibility, but the negative influence of personal risk is empirically supported for both variables. Finally, the results obtained related to social and time risk are contradictory. Social risk negatively influences entrepreneurship desirability, but a positive effect is observed on the feasibility to create a business. For its part, the empirical evidence obtained does not support any effect of the time risk on the perceived feasibility of starting a business, but there is a positive on entrepreneurship desirability. These results, which are contrary to the traditional concept of risk as a barrier to entrepreneurship, are justified by the vocational nature of this behaviour and by the social sacrifices that are sometimes necessary to be able to make a business work

Intención de emprendimiento: ventajas e inconvenientes percibidos

ABSTRAC: Purpose - Based on the Theory of Planned Behaviour, the purpose of this paper is to analyse the influence of the advantages and disadvantages of entrepreneurship surrounding the entrepreneurial intention on a university context. Design/methodology/approach - To test the hypothesis it is used a quantitative research. With a structural equations approach, it is explored the psychological mechanisms that could affect to the entrepreneurial intentions of university students. Findings - The results obtained show that the advantages related to entrepreneurship, in particular personal rewards, influence positively on the entrepreneurial attitude. However, the disadvantages, in particular economic aspects, have a negative effect. Additionally, the authors test that the gender and the academic training have a moderate effect on the variables which influence on the entrepreneurial intention. Originality/value - This paper contributes to the literature on entrepreneurship in two important aspects. First, it goes into detail about the influence that perceived advantages and disadvantages of starting a new business has on entrepreneurial intentions. Second, the authors examine relevant and special collective, university students that try to decide their professional future and, hence, it is a critical period to decide the startup of a new business.RESUMEN: Propósito - Con la Teoría de Comportamiento Planificado como marco de referencia este trabajo analiza la influencia de las ventajas e inconvenientes asociados al emprendimiento sobre la intención emprendedora en un contexto universitario. Diseño/metodología - Para la contrastación empírica de las hipótesis planteadas se realiza una investigación de naturaleza cuantitativa mediante la cual se exploran los mecanismos psicológicos que podrían guiar las intenciones de emprendimiento de los estudiantes universitarios. Resultados - Los resultados obtenidos ponen de manifiesto que las ventajas asociadas al emprendimiento, en especial las recompensas personales, influyen positivamente en la actitud emprendedora, mientras que los inconvenientes asociados al emprendimiento, y en particular los aspectos económicos, ejercen un efecto negativo. Asimismo, se constata que el sexo y los estudios cursados tienen un efecto moderador en las variables que afectan a la intención emprendedora. Originalidad/Valor - El presente trabajo aporta dos contribuciones fundamentales a la literatura sobre emprendimiento. Por un lado, profundiza en la comprensión de la influencia que tienen en la decisión de emprender las percepciones de los individuos respecto a las ventajas e inconvenientes de crear un negocio propio. Por otro lado, se examina un colectivo de especial relevancia en el ámbito del emprendimiento, como son los estudiantes universitarios, que se encuentran en situación de encaminar su futuro profesional y, por tanto, en un momento crítico para la decisión de crear una empresa propia

Involvement of PPARy in the antitumoral action of cannabinoids on hepatocellular carcinoma

Cannabinoids exert antiproliferative effects in a wide range of tumoral cells, including hepatocellular carcinoma (HCC) cells. In\ud this study, we examined whether the PPARc-activated pathway contributed to the antitumor effect of two cannabinoids,\ud D9-tetrahydrocannabinol (THC) and JWH-015, against HepG2 and HUH-7 HCC cells. Both cannabinoids increased the activity\ud and intracellular level of PPARc mRNA and protein, which was abolished by the PPARc inhibitor GW9662. Moreover, genetic\ud ablation with small interfering RNA (siRNA), as well as pharmacological inhibition of PPARc decreased the cannabinoid-induced\ud cell death and apoptosis. Likewise, GW9662 totally blocked the antitumoral action of cannabinoids in xenograft-induced HCC\ud tumors in mice. In addition, PPARc knockdown with siRNA caused accumulation of the autophagy markers LC3-II and p62,\ud suggesting that PPARc is necessary for the autophagy flux promoted by cannabinoids. Interestingly, downregulation of the\ud endoplasmic reticulum stress-related protein tribbles homolog 3 (TRIB3) markedly reduced PPARc expression and induced p62\ud accumulation, which was counteracted by overexpression of PPARc in TRIB3-knocked down cells. Taken together, we\ud demonstrate for the first time that the antiproliferative action of the cannabinoids THC and JWH-015 on HCC, in vitro and in vivo,\ud are modulated by upregulation of PPARc-dependent pathways

Nuevas terapias en esclerosis múltiple: la remielinización como nueva estrategia terapéutica

La esclerosis múltiple (EM) es una enfermedad crónica desmielinizante de origen autoinmune y de etiología y evolución heterogéneas. En la EM, la inflamación y el proceso de desmielinización llevan a la neurodegeneración y a la progresión de la discapacidad. En la actualidad, las terapias utilizadas en clínica, basadas en la inmunomodulación y la inmunosupresión, consiguen restrasar el paso a la fase progresiva. En los últimos años, el estudio de los mecanismos endógenos de reclutamiento, diferenciación y formación de mielina de las células precursoras de oligodendrocitos (OPCs) han permitido identificar nuevas dianas terapéuticas, como los receptores de la proteína LINGO-1 y del anticuerpo monoclonal rHIgM22 en la superficie de OPCs y los receptores β- estrogénicos. También se ha estudiado el papel de las células madre mesenquimales en la prevención de la neurodegeneración y la promoción de la remielinización. Los resultados obtenidos en modelos animales de la enfermedad han confirmado el enorme potencial de la remielinización como nueva estrategia terapéutica