49 research outputs found

    The centrosome and spindle as a ribonucleoprotein complex

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    Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Chromosome Research 19 (2011): 367-376, doi:10.1007/s10577-011-9186-7.The presence of nucleic acids in centrosomes and the spindle have been proposed, observed, and reported since the 1950s. Why did the subject remain, perhaps even until today, such a controversial issue? The explanation is manifold, and includes legitimate concern over contamination from other cellular compartments in biochemical preparations. With a typically high background of cytoplasmic ribosomes, even microscopic images of stained intact cells could be difficult to interpret. Also, evidence for RNA and DNA in centrosomes accumulated for approximately 40 years but was interspersed with contradictory studies, primarily regarding the presence of DNA (reviewed in Johnson and Rosenbaum, 1991; Marshall and Rosenbaum, 2000). Perhaps less tangible but still a likely cause for lingering controversy is that the presence of nucleic acids in the spindle or centrosomes will require us to look differently at these structures from a functional, and more to the point, evolutionary standpoint.This work was supported by grants from the NIH (GM088503) and NSF (MCB0843092) to MCA

    De-Implementation of Detrimental Feeding Practices in Childcare: Mixed Methods Evaluation of Community Partner Selected Strategies

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    This pilot evaluated strategies to decrease detrimental feeding practices in early care and education, which are hypothesized to compete with evidence-based feeding and obesity prevention practices. This study made two key comparisons: (1) a between-site comparison of sites receiving (a) no implementation or de-implementation strategies (i.e., Basic Support; B), (b) implementation strategies only (i.e., Enhanced Support; E), and (c) implementation and de-implementation strategies (i.e., De-implementation + Enhanced Support; D + E) and (2) a within-site pre-post comparison among sites with D + E. At nutrition lessons, the D + E group had more Positive Comments (Hedege’s g = 0.60) and higher Role Model fidelity (Hedege’s g = 1.34) compared to the E group. At meals, assistant teachers in the D + E group had higher Positive Comments than in the B group (g = 0.72). For within-group comparisons, the D + E group decreased Negative Comments (t(19) = 2.842, p = 0.01), increased Positive Comments (t(20) = 2.314, p = 0.031), and improved use of the program mascot at nutrition lessons (t(21) = 3.899, p = 0.001). At meals, lead teachers’ Negative Comments decreased (t(22) = 2.73, p = 0.01). Qualitative data identified strengths and opportunities for iteration. Despite a COVID interruption, mid-point comparisons and qualitative feedback suggest promise of the de-implementation strategy package

    Endocannabinoid signalling modulates susceptibility to traumatic stress exposure

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    Stress is a ubiquitous risk factor for the exacerbation and development of affective disorders including major depression and posttraumatic stress disorder. Understanding the neurobiological mechanisms conferring resilience to the adverse consequences of stress could have broad implications for the treatment and prevention of mood and anxiety disorders. We utilize laboratory mice and their innate inter-individual differences in stress-susceptibility to demonstrate a critical role for the endogenous cannabinoid 2-arachidonoylglycerol (2-AG) in stress-resilience. Specifically, systemic 2-AG augmentation is associated with a stress-resilient phenotype and enhances resilience in previously susceptible mice, while systemic 2-AG depletion or CB1 receptor blockade increases susceptibility in previously resilient mice. Moreover, stress-resilience is associated with increased phasic 2-AG-mediated synaptic suppression at ventral hippocampal-amygdala glutamatergic synapses and amygdala-specific 2-AG depletion impairs successful adaptation to repeated stress. These data indicate amygdala 2-AG signalling mechanisms promote resilience to adverse effects of acute traumatic stress and facilitate adaptation to repeated stress exposure
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