Search

Emotional tears have been proposed to serve as a signal of distress, appeasement, and helplessness, which promotes prosocial responses in observers. They may also facilitate the perception of sadness. A still unanswered question is what information tears convey about emotional states when they are combined with different muscular facial expressions. The current study evaluated three hypotheses: Tears facilitate inferences about (a) emotion intensity in general (b) sadness in particular, or (c) helplessness-related appraisal and behavioral intentions. In the first experiment, participants viewed pictures of (non)tearful real and artificial faces displaying anger, disgust, fear, happiness, sadness, surprise, and neutral state. They had to report which of the seven expressions they recognized, and to rate its intensity, sincerity, and felt empathy. Tears appeared to facilitate the perception of sadness, but also of anger and fear, while they decreased the perception of disgust and surprise. The ratings of the intensity, the perceived sincerity, and the experienced empathy followed a similar pattern. In the second experiment, participants had to indicate if briefly (50 ms) presented (non)tearful faces showed a particular expression, and we measured their accuracy and reaction times. The results of the first experiment were not corroborated. Overall, the findings lend most support to the appraisal/behavioral intentions hypothesis and less support for the intensity and the sadness enhancement hypotheses. [ABSTRACT FROM AUTHOR]

Researchers have found that men's facial hair may have certain signaling functions connected with intrasexual competition and intersexual attractiveness. The interesting issue is whether men's and women's preferences for men's facial hair may be considered a reflection of their intuitive knowledge about these functions. The aim of the presented studies was to analyze women's and men's preferences regarding men's facial hair using questions with a dichotomous answer format (Study 1 and Study 2) and pictorial stimuli (Study 2). In both studies, women were asked to indicate their preferences for men's facial hair. Men were asked to report preferences for facial hair in themselves and in other men, as well as to report their actual appearance of facial hair. The results showed that women's preferences for men's facial hair were ambiguous, while men preferred facial hair for themselves and had a lower inclination to prefer facial hair in other men. It suggests that men may be aware of some aspects of signaling functions of facial hair, especially these connected with intrasexual competition. [ABSTRACT FROM AUTHOR]

Peptidoglycan (PG) is an essential molecule for the survival of bacteria, and thus, its biosynthesis and remodeling have always been in the spotlight when it comes to the development of antibiotics. The peptidoglycan polymer provides a protective function in bacteria, but at the same time is continuously subjected to editing activities that in some cases lead to the release of peptidoglycan fragments (i.e., muropeptides) to the environment. Several soluble muropeptides have been reported to work as signaling molecules. In this review, we summarize the mechanisms involved in muropeptide release (PG breakdown and PG recycling) and describe the known PG-receptor proteins responsible for PG sensing. Furthermore, we overview the role of muropeptides as signaling molecules, focusing on the microbial responses and their functions in the host beyond their immunostimulatory activity.

Peptidoglycan (PG) is an essential molecule for the survival of bacteria, and thus, its biosynthesis and remodeling have always been in the spotlight when it comes to the development of antibiotics. The peptidoglycan polymer provides a protective function in bacteria, but at the same time is continuously subjected to editing activities that in some cases lead to the release of peptidoglycan fragments (i.e., muropeptides) to the environment. Several soluble muropeptides have been reported to work as signaling molecules. In this review, we summarize the mechanisms involved in muropeptide release (PG breakdown and PG recycling) and describe the known PG-receptor proteins responsible for PG sensing. Furthermore, we overview the role of muropeptides as signaling molecules, focusing on the microbial responses and their functions in the host beyond their immunostimulatory activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Cardiac diseases are the leading cause of mortality and morbidity worldwide. Mounting evidence suggests that transglutaminases (TGs), tissue TG (TG2) in particular, are involved in numerous molecular responses underlying the pathogenesis of cardiac diseases. The TG family has several intra- and extracellular functions in the human body, including collagen cross-linking, angiogenesis, cell growth, differentiation, migration, adhesion as well as survival. TGs are thiol- and calcium-dependent acyl transferases that catalyze the formation of a covalent bond between the γ-carboxamide group of a glutamine residue and an amine group, thus increasing the stability, rigidity, and stiffness of the myocardial extracellular matrix (ECM). Excessive accumulation of cross-linked collagen leads to increase myocardial stiffness and fibrosis. Beyond TG2 extracellular protein cross-linking action, increasing evidence suggests that this pleiotropic TG isozyme may also promote fibrotic diseases through cell survival and profibrotic pathway activation at the signaling, transcriptional and translational levels. Due to its multiple functions and localizations, TG2 fulfils critical yet incompletely understood roles in myocardial fibrosis and associated heart diseases, such as cardiac hypertrophy, heart failure, and age-related myocardial stiffness under several conditions. This review summarizes current knowledge and existing gaps regarding the ECM-dependent and ECM-independent roles of TG2 and highlights the therapeutic prospects of targeting TG2 to treat cardiac diseases. [ABSTRACT FROM AUTHOR]