C/EBPβ controls exercise-induced cardiac growth and protects against pathological cardiac remodeling

The heart has the ability to grow in size in response to exercise, but little is known about the transcriptional mechanisms underlying physiological hypertrophy. Adult cardiomyocytes have also recently been proven to hold the potential for proliferation, a process that could be of great importance for regenerative medicine. Using a unique RT-PCR-based screen against all transcriptional components, we showed that C/EBP{beta} was downregulated with exercise, whereas the expression of CITED4 was increased. Reduction of C/EBP{beta} in vitro and in vivo resulted in a phenocopy of endurance exercise with cardiomyocyte hypertrophy and proliferation. This proliferation was mediated, at least in part, by the increased CITED4. Importantly, mice with reduced cardiac C/EBP{beta} levels displayed substantial resistance to cardiac failure upon pressure overload. These data indicate that C/EBP{beta} represses cardiomyocyte growth and proliferation in the adult mammalian heart and that reduction in C/EBP{beta} is a central signal in physiologic hypertrophy and proliferation

The perception of attractiveness and trustworthiness in male faces affects hypothetical voting decisions differently in wartime and peacetime scenarios

Facial appearance of candidates has been linked to real election outcomes. Here we extend these findings by examining the contributions of attractiveness and trustworthiness in male faces to perceived votability. We first use real faces to show that attractiveness and trustworthiness are positively and independently related to perceptions of good leadership (rating study). We then show that computer graphic manipulations of attractiveness and trustworthiness influence choice of leader (Experiments 1 and 2). Finally, we show that changing context from wartime to peacetime can affect which face receives the most votes. Attractive faces were relatively more valued for wartime and trustworthy faces relatively more valued for peacetime (Experiments 1 and 2). This pattern suggests that attractiveness, which may indicate health and fitness, is perceived to be a useful attribute in wartime leaders, whereas trustworthiness, which may indicate prosocial traits, is perceived to be more important during peacetime. Our studies highlight the possible role of facial appearance in voting behaviour and the role of attributions of attractiveness and trust. We also show that there may be no general characteristics of faces that make them perceived as the best choice of leader; leaders may be chosen because of characteristics that are perceived as the best for leaders to possess in particular situations