Design, manufacturing and testing of a green non-isocyanate polyurethane prosthetic heart valve.

The sole effective treatment for most patients with heart valve disease is valve replacement by implantation of mechanical or biological prostheses. However, mechanical valves represent high risk of thromboembolism, and biological prostheses are prone to early degeneration. In this work, we aim to determine the potential of novel environmentally-friendly non-isocyanate polyurethanes (NIPUs) for manufacturing synthetic prosthetic heart valves. Polyhydroxyurethane (PHU) NIPUs are synthesized via an isocyanate-free route, tested in vitro, and used to produce aortic valves. PHU elastomers reinforced with a polyester mesh show mechanical properties similar to native valve leaflets. These NIPUs do not cause hemolysis. Interestingly, both platelet adhesion and contact activation-induced coagulation are strongly reduced on NIPU surfaces, indicating low thrombogenicity. Fibroblasts and endothelial cells maintain normal growth and shape after indirect contact with NIPUs. Fluid-structure interaction (FSI) allows modeling of the ideal valve design, with minimal shear stress on the leaflets. Injection-molded valves are tested in a pulse duplicator and show ISO-compliant hydrodynamic performance, comparable to clinically-used bioprostheses. Poly(tetrahydrofuran) (PTHF)-NIPU patches do not show any evidence of calcification over a period of 8 weeks. NIPUs are promising sustainable biomaterials for the manufacturing of improved prosthetic valves with low thrombogenicity.

Prefrontal mediation of emotion regulation in social anxiety disorder during laughter perception.

Social anxiety disorder (SAD) is characterized by negatively biased perception of social cues and deficits in emotion regulation. While negatively biased perception is thought to maintain social anxiety, emotion regulation represents an ability necessary to overcome both biased perception and social anxiety. Here, we used laughter as a social threat in a functional magnetic resonance imaging (fMRI) study to identify cerebral mediators linking SAD with attention and interpretation biases and their modification through cognitive emotion regulation in the form of reappraisal. We found that reappraisal abolished the negative laughter interpretation bias in SAD and that this process was directly mediated through activation patterns of the left dorsolateral prefrontal cortex (DLPFC) serving as a cerebral pivot between biased social perception and its normalization through reappraisal. Connectivity analyses revealed reduced prefrontal control over threat-processing sensory cortices (here: the temporal voice area) during cognitive emotion regulation in SAD. Our results indicate a central role for the left DLPFC in SAD which might represent a valuable target for future research on interventions either aiming to directly modulate cognitive emotion regulation in SAD or to evaluate its potential as physiological marker for psychotherapeutic interventions relying on emotion regulation.

Targeting Feeding and Eating Behaviors: Development of the Feeding Dynamic Intervention for Caregivers of 2- to 5-Year-Old Children.

Targeting feeding dynamics, a concept centered on the roles and interaction of the caregiver and child in a feeding relationship, may have significant potential for obesity intervention. The aim of this paper is to describe the 3-phase development of the Feeding Dynamics Intervention (FDI), an acceptability and feasibility study on implementing the feeding dynamic roles (Study 1), development of the FDI content (Study 2), and a pilot study on use of the 6-lesson FDI to promote behaviors consistent with a feeding dynamic approach (Study 3). Sample population was mothers with young children, 2-5 years old. An effect size (Hedges' g) greater than 0.20 was seen in more than half (57%) of maternal feeding behaviors, with the largest effect sizes (Hedges' g ≥ 0.8) occurring with behaviors that represent the mother adopting her roles of determining what food is served, not using food as a reward, and not controlling her child's intake. There was a significant decline in Pressure to Eat behaviors (2.9 versus 2.2, p < 0.01) and Monitoring (4.1 versus 3.5, p < 0.001). The FDI emerged as an acceptable and implementable intervention. Future studies need to investigate effects of the FDI on the child's eating behaviors, self-regulation of energy intake, and anthropometrics.

Laughter perception in social anxiety.

BACKGROUND: Laughter is a powerful signal of social acceptance or rejection while the fear of being embarrassed and humiliated is central in social anxiety (SA). This type of anxiety is associated with cognitive biases indicating increased sensitivity to social threat as well as with deficits in emotion regulation. Both are thought to be implicated in the maintenance of social anxiety. METHOD: Using laughter as a novel stimulus, we investigated cognitive biases and their modulation through emotion regulation and cue ambiguity in individuals with varying degrees of SA (N = 60). RESULTS: A combination of a negative laughter interpretation bias and an attention bias away from joyful/social inclusive laughter in SA was observed. Both biases were not attributable to effects of general anxiety and were closely correlated with the concept of gelotophobia, the fear of being laughed at. DISCUSSION: Thus, our study demonstrates altered laughter perception in SA. Furthermore, it highlights the usefulness of laughter as a highly prevalent social signal for future research on the interrelations of interpretation and attention biases in SA and their modulation through emotion regulation.

They are laughing at me: cerebral mediation of cognitive biases in social anxiety.

The fear of embarrassment and humiliation is the central element of social anxiety. This frequent condition is associated with cognitive biases indicating increased sensitivity to signals of social threat, which are assumed to play a causal role in the maintenance of social anxiety. Here, we employed laughter, a potent medium for the expression of acceptance and rejection, as an experimental stimulus in participants selected for varying degrees of social anxiety to identify cerebral mediators of cognitive biases in social anxiety using functional magnetic resonance imaging in combination with mediation analysis. We directly demonstrated that cerebral activation patterns within the dorsal attention network including the left dorsolateral and dorsomedial prefrontal cortex mediate the influence of social anxiety on laughter perception. This mediation proved to be specific for social anxiety after correction for measures of general state and trait anxiety and occurred most prominently under bimodal audiovisual laughter presentation when compared with monomodal auditory or visual laughter cues. Considering the possibility to modulate cognitive biases and cerebral activity by neuropsychological trainings, non-invasive electrophysiological stimulation and psychotherapy, this study represents a starting point for a whole line of translational research projects and identifies promising targets for electrophysiological interventions aiming to alleviate cognitive biases and symptom severity in social anxiety.