Establishing Riboglow-FLIM to visualize noncoding RNAs inside live zebrafish embryos.

The central role of RNAs in health and disease calls for robust tools to visualize RNAs in living systems through fluorescence microscopy. Live zebrafish embryos are a popular system to investigate multicellular complexity as disease models. However, RNA visualization approaches in whole organisms are notably underdeveloped. Here, we establish our RNA tagging and imaging platform Riboglow-FLIM for complex cellular imaging applications by systematically evaluating FLIM capabilities. We use adherent mammalian cells as models for RNA visualization. Additional complexity of analyzing RNAs in whole mammalian animals is achieved by injecting these cells into a zebrafish embryo system for cell-by-cell analysis in this model of multicellularity. We first evaluate all variable elements of Riboglow-FLIM quantitatively before assessing optimal use in whole animals. In this way, we demonstrate that a model noncoding RNA can be detected robustly and quantitatively inside live zebrafish embryos using a far-red Cy5-based variant of the Riboglow platform. We can clearly resolve cell-to-cell heterogeneity of different RNA populations by this methodology, promising applicability in diverse fields.

Psilocybin's Potential Mechanisms in the Treatment of Depression: A Systematic Review.

Evidence suggests that psilocybin has therapeutic benefit for treating depression. However, there is little consensus regarding the mechanism by which psilocybin elicits antidepressant effects. This systematic review summarizes existing evidence. Ovid MEDLINE, EMBASE, psychINFO, and Web of Science were searched, for both human and animal studies, using a combination of MeSH Terms and free-text keywords in September 2021. No other mood disorders or psychiatric diagnoses were included. Original papers in English were included. The PRISMA framework was followed for the screening of papers. Two researchers screened the retrieved articles from the literature search, and a third researcher resolved any conflicts. Of 2,193 papers identified, 49 were selected for full-text review. 14 articles were included in the qualitative synthesis. Six supported psilocybin's mechanism of antidepressant action via changes to serotonin or glutamate receptor activity and three papers found an increase in synaptogenesis. Thirteen papers investigated changes in non-receptor or pathway-specific brain activity. Five papers found changes in functional connectivity or neurotransmission, most commonly in the hippocampus or prefrontal cortex. Several neuroreceptors, neurotransmitters, and brain areas are thought to be involved in psilocybin's ability to mitigate depressive symptoms. Psilocybin appears to alter cerebral blood flow to the amygdala and prefrontal cortex, but the evidence on changes in functional connectivity and specific receptor activity remains sparse. The lack of consensus between studies suggests that psilocybin's mechanism of action may involve a variety of pathways, demonstrating the need for more studies on psilocybin's mechanism of action as an antidepressant.

Visualizing orthogonal RNAs simultaneously in live mammalian cells by fluorescence lifetime imaging microscopy (FLIM).

Visualization of RNAs in live cells is critical to understand biology of RNA dynamics and function in the complex cellular environment. Detection of RNAs with a fluorescent marker frequently involves genetically fusing an RNA aptamer tag to the RNA of interest, which binds to small molecules that are added to live cells and have fluorescent properties. Engineering efforts aim to improve performance and add versatile features. Current efforts focus on adding multiplexing capabilities to tag and visualize multiple RNAs simultaneously in the same cell. Here, we present the fluorescence lifetime-based platform Riboglow-FLIM. Our system requires a smaller tag and has superior cell contrast when compared with intensity-based detection. Because our RNA tags are derived from a large bacterial riboswitch sequence family, the riboswitch variants add versatility for using multiple tags simultaneously. Indeed, we demonstrate visualization of two RNAs simultaneously with orthogonal lifetime-based tags.

The influence of traffic on air quality in an urban neighborhood: a community-university partnership.

OBJECTIVES: We evaluated the spatial and temporal patterns of traffic-related air pollutants in an urban neighborhood to determine factors contributing to elevated concentrations and to inform environmental justice concerns. METHODS: In the summer of 2007, we continuously monitored multiple air pollutants at a community site in the Mission Hill neighborhood of Boston, Massachusetts, and local high school students conducted mobile continuous monitoring throughout the neighborhood. We used regression models to explain variability in concentrations, considering various attributes of traffic, proximity to major roadways, and meteorology. RESULTS: Different attributes of traffic explained variability in fixed-site concentrations of ultrafine particles, fine particulate matter, and black carbon, with diurnal patterns and meteorological effects indicative of a greater local effect on ultrafine particles and black carbon. Mobile monitoring demonstrated that multiple traffic variables predict elevated levels of ultrafine particles, with concentrations of ultrafine particles decreasing by 50% within 400 meters of 2 major roadways. CONCLUSIONS: Unlike fine particulate matter, ultrafine particles demonstrate significant spatial and temporal variability within an urban neighborhood, contributing to environmental justice concerns, and patterns can be well characterized with a community-based participatory research design.