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Aim: To compare the physiological behavior of mesenchymal stem/stromal cells (MSCs) within an expandable tissue-mimetic 3D system relative to in vitro expansion in a traditional 2D system. Methods: Adipose-derived MSCs (ASCs) were continuously cultured for 6 weeks on either 2D culture plastic or in a 3D hydrogel system that eliminated subculturing. ASCs were assessed for senescence, 'stem-like' MSC markers, and ability for their secretome to augment a secondary cell population. Results: The 3D hydrogel system resulted in an enhanced retention of more regenerative, nonsenescent ASC populations that exhibited increased expression of 'stem-like' MSC surface markers. Conclusion: This study introduces a proof-of-concept design for a novel modular 3D system that can improve in vitro expansion of stem-like cell populations for future regenerative therapies. Novel tissue-mimetic 3D hydrogel system enhances the retention of nonsenescent ASC populations in vitro for up to 6 weeks in culture and eliminates the need to subculture, improving regenerative capacity of ASCs and their secreted biologics. [ABSTRACT FROM AUTHOR]

There has been increasing interest in food- and dietary supplement-based materials that may support healthy cognition. However, few studies have quantitatively measured bioavailability, bioactivity, or cognitive short- and long-term effects of these materials against placebo. Earlier clinical studies reported ability of coffee cherry extract (CCE) to a.) reduce levels of reactive oxygen species (ROS) in human blood and b.) to increase serum and exosomal levels of brain-derived neurotrophic factor (BDNF), a neuroprotein essential for neurogenesis. Here, we examined CCE influence on cognitive performance. Seventy-one adults with mild cognitive decline completed this double blind, randomized, placebo-controlled, 28-day regimen. Participants engaged in a cognitive challenge that involved working memory processes. Our results suggest that effects of CCE were notable during the first week and persisted throughout the study period. Specifically, participants on the CCE regimens had significant reductions in reaction time compared to placebo when comparing baseline to days 7 and 28 (p = 0.040, partial η2  = 0.130). A main effect of group was not identified for accuracy; however, strong trends were noted between the placebo group and two of the three CCE groups. These results suggest CCE, when taken in the morning or twice per day, is associated with improvements in reaction times and trends toward indications of improved accuracy. Although further research is required, these observations may be indicative of underlying processes such as increased processing speed, sustained attention, and/or focus. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize the functional activation of the neural correlates of voluntary regulation of emotion in soldiers both with and without chronic mild traumatic brain injury (mTBI). Using functional magnetic resonance imaging (fMRI) and a battery of cognitive and psychological health measures, we assessed differences between active-duty U.S. soldiers with chronic mTBI (n = 37) and without (Controls, n = 35). Participants were instructed to maintain (passively view), enhance, and suppress emotions associated with negative and neutral visual stimuli. The mTBI group showed significantly greater clinical symptoms, but only a mild decrement in attention. Group contrasts, while controlling for posttraumatic stress disorder (PTSD) symptoms, revealed a differential neural activation pattern compared to controls, but only during the enhance condition. Specifically, the mTBI group showed greater activation in the precentral gyrus, postcentral gyrus, inferior parietal lobe, insula, and superior temporal gyrus. Finally, the effect of PTSD symptoms during the enhance condition was associated with accentuated activation of the frontal and limbic regions implicated in both emotion regulation and PTSD. Hyperactivation of neural regions in the mTBI group during the enhance condition may reflect vigilance towards negative contextual stimuli and/or poor strategy that might result in suboptimal allocation of resources to regulate emotions. [ABSTRACT FROM AUTHOR]

In this study, the connection between sexual orientation microaggressions and posttraumatic stress disorder (PTSD) symptoms has been evaluated. The researchers measured the perception and impact of homonegative microaggressions, with the Homonegative Microaggression Scale (Wright & Wegner, 2012), as well as the severity of posttraumatic symptoms, with the Posttraumatic Stress Disorder Checklist—Civilian Version (Weathers, Litz, Huska, & Keane, 1994). Ninety lesbian, gay, and bisexual (LGB) and 80 heterosexual participants were recruited through convenience sampling and online LGB communities. Completion of the measures occurred through an online survey system at the convenience of the participants. The results of the study revealed a positive correlation between reported posttraumatic symptoms and microaggressive experiences, and between posttraumatic symptoms and their perceived impact on participants. A difference between LGB and heterosexual participants' experiences of microaggressions was seen, as well as a difference in reported posttraumatic symptoms related to homonegative experiences. The findings were all statistically significant and suggested that there may be a link between homonegative microaggressions and traumatic stress symptoms, which may demonstrate the potential for insidious trauma to be a factor in LGB minority stress. [ABSTRACT FROM PUBLISHER]

The rapid growth of regenerative medicine and drug delivery fields has generated a strong need for improved polymeric materials that degrade at a controlled rate into safe, non-cytotoxic by-products. Polyurethane thermoplastic elastomers offer several advantages over other polymeric materials including tunable mechanical properties, excellent fatigue strength, and versatile processing. The variable segmental chemistry in developing resorbable polyurethanes also enables fine control over the degradation profile as well as the mechanical properties. Linear aliphatic isocyanates are most commonly used in biodegradable polyurethane formulations; however, these aliphatic polyurethanes do not match the mechanical properties of their aromatic counterparts. In this study, a novel poly(ester urethane) (PEsU) synthesized with biodegradable aromatic isocyanates based on glycolic acid was characterized for potential use as a new resorbable material in medical devices. Infrared spectral analysis confirmed the aromatic and phase-separated nature of the PEsU. Uniaxial tensile testing displayed stress-strain behavior typical of a semi-crystalline polymer above its Tg, in agreement with calorimetric findings. PEsU outperformed aliphatic PCL-based polyurethanes likely due to the enhanced cohesion of the aromatic hard domains. Accelerated degradation of the PEsU using 0.1M sodium hydroxide resulted in hydrolysis of the polyester soft segment on the surface, reduced molecular weight, surface cracking, and a 30% mass loss after four weeks. Calorimetric studies indicated a disruption of the soft segment crystallinity after incubation which corresponded with a drop in initial modulus of the PEsU. Finally, cytocompatibility testing with 3T3 mouse fibroblasts exhibited cell viability on PEsU films comparable to a commercial poly(ether urethane urea) after 24h followed by 85% cell viability at 72h. Overall, this new resorbable polyurethane shows strong potential for use in wide range of biomedical applications. [ABSTRACT FROM AUTHOR]

The neurophysiology underlying the Behavioral Activation and Behavioral Inhibition Systems (BAS and BIS) and the impact of the strength of these systems on affective processing have received increased attention over the last 25 years. Specifically, left-frontal brain regions have been implicated in BAS strength as well as the experience of positive-approach affect (such as happiness). Conversely, BIS strength and negative-avoidance affect (such as fear) appear to be modulated by right-frontal brain regions. Taken together, it is not surprising that BAS and BIS strength have been associated with positive and negative affective biases, respectively, to emotional stimuli that do not involve extensive human interaction. The present investigation was designed to extend these findings by assessing the relationship between BAS and BIS strength on the perception of emotional interactions. Participants ( n = 67) were shown four 2-min film clips that depict an individual exerting dominance over one or more other individuals. Each participant rated the clips with regard to valence, arousal, and dominance parameters, and then indicated the person(s) in the movie with whom they identified (i.e., the dominant individual or submissive individual[s]). Consistent with a priori hypotheses, persons identifying with the submissive character scored significantly higher on BIS sensitivity. BAS strength and BIS/BAS ratio, conversely, were not associated with character identification. Also as predicted, identification with the dominant movie character was associated with increased positive affect and feelings of dominance. Interestingly, although not hypothesized, trait dominance was also associated with character identification by virtue of being positively associated with BAS and PA and negatively associated with BIS and NA. [ABSTRACT FROM AUTHOR]