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Morphogen-mediated signaling is critical for proper organ development and stem cell function, and well-characterized mechanisms spatiotemporally limit the expression of ligands, receptors, and ligand-binding cell-surface glypicans. Here, we show that in the developing Drosophila ovary, canonical Wnt signaling promotes the formation of somatic escort cells (ECs) and their protrusions, which establish a physical permeability barrier to define morphogen territories for proper germ cell differentiation. The protrusions shield germ cells from Dpp and Wingless morphogens produced by the germline stem cell (GSC) niche and normally only received by GSCs. Genetic disruption of EC protrusions allows GSC progeny to also receive Dpp and Wingless, which subsequently disrupt germ cell differentiation. Our results reveal a role for canonical Wnt signaling in specifying the ovarian somatic cells necessary for germ cell differentiation. Additionally, we demonstrate the morphogen-limiting function of this physical permeability barrier, which may be a common mechanism in other organs across species.

Our computational developments and analyses on experimental images are designed to evaluate the effectiveness of chemical spraying via unmanned aerial vehicle (UAV). Our evaluations are in accord with the two perspectives of color-complexity: color variety within a color system and color distributional geometry on an image. First, by working within RGB and HSV color systems, we develop a new color-identification algorithm relying on highly associative relations among three color-coordinates to lead us to exhaustively identify all targeted color-pixels. A color-dot is then identified as one isolated network of connected color-pixel. All identified color-dots vary in shapes and sizes within each image. Such a pixel-based computing algorithm is shown robustly and efficiently accommodating heterogeneity due to shaded regions and lighting conditions. Secondly, all color-dots with varying sizes are categorized into three categories. Since the number of small color-dot is rather large, we spatially divide the entire image into a 2D lattice of rectangular. As such, each rectangle becomes a collective of color-dots of various sizes and is classified with respect to its color-dots intensity. We progressively construct a series of minimum spanning trees (MST) as multiscale 2D distributional spatial geometries in a decreasing-intensity fashion. We extract the distributions of distances among connected rectangle-nodes in the observed MST and simulated MSTs generated under the spatial uniformness assumption. We devise a new algorithm for testing 2D spatial uniformness based on a Hierarchical clustering tree upon all involving MSTs. This new tree-based p-value evaluation has the capacity to become exact.

Abstract Background Giant retinal tear is usually challenging among retinal detachment with recurrent rate up to 45%. Here we presented a case of giant retinal tear being treated by microincision vitrectomy and retinal tacks fixation. Case presentation A 53-year-old male presented to our hospital with blurred vision of his right eye for one week with floaters and obscured sensation over nasal visual field. Ocular examination showed a 120 degree giant tear with large inverted flap and retinal detachment of his right eye. The BCVA was only naming digit. Under the impression of giant retinal tear with retinal detachment, 23-gauge pars plana vitrectomy were performed using Constellation high speed vitrectomy system and Topcon non-contact wide angle viewing system. During surgery, the vitreous was removed and perfluorocarbon liquids (PFCL) was injected to help unfolding the large inverted retinal flap. Three retinal tacks were applied to help fixating the large inverted retinal flap. Then, fluid-gas exchange, endolaser photocoagulation and intraocular silicone oil tamponade were performed as well. Initial reattachment of his right retina was achieved and his best corrected visual acuity improved to 0.3 of his right eye postoperatively. There was no recurrent retinal detachment during follow up period of 19 months. Conclusions Primary microincision vitrectomy using wide-angle viewing system with intraoperative perfluorocarbon liquids (PFCL) assistant, retinal tacks fixation and intraocular silicone oil tamponade appears to be safe and feasible for managing giant retinal tear with retinal detachment.

Rhodiola rosea L. (R. rosea) is one of the most beneficial medicinal plants and it is studied as an adaptogen. This study aims to evaluate the neuroprotective activity of compounds extracted from the root of R. rosea against methylglyoxal (MG)-induced apoptosis in neuro-2A (N2A) cells. The root of R. rosea was extracted with ethanol and partitioned with water, ethyl acetate, and n-butanol fractions to evaluate acetylcholinesterase (AChE) inhibitory activity and neuroprotective activity. The ethyl acetate fraction exhibited the highest values of AChE inhibitory activity (49.2% ± 3%) and cell viability (50.7% ± 4.8%) for neuroprotection. The structure identification of the most potential fraction (ethyl acetate fraction) revealed 15 compounds, consisting of three tannins, five flavonoids, and seven phenolics by infrared spectroscopy, nuclear magnetic resonance, and mass spectroscopy. All compounds were evaluated for their neuroprotective activity. Salidroside had the most potential neuroprotective activity. Gallic acid and methyl gallate had potential cytotoxicity in N2A cells. This study showed that R. rosea might have potential neuroprotective activities.

A new 8,17-epoxybriarane, briastecholide O (1), was isolated from an encrusting algae-containing cultured octocoral Briareum stechei. Moreover, wild-type B. stechei collected from Okinawan waters yielded a new 8,17-epoxybriarane, briastecholide P (2), along with two known analogs, namely, briaexcavatins G (3) and X (4). Single-crystal X-ray diffraction was conducted to determine the absolute configurations of 2 – 4 , while the structure of 1 was established by spectroscopic elucidation. Briaranes 1 and 3 were active in enhancing the growth of MG-63 human mesenchymal stem cells. [Display omitted] • New briaranes, briastecholides O (1) and P (2), were isolated from Briareum stechei. • The absolute configuration of briarane 2 was determined via X-ray analysis. • Briarane 1 enhanced the growth of MG-63 human mesenchymal stem cells. [ABSTRACT FROM AUTHOR]

The mRNA 5'-cap structure removal by the decapping enzyme DCP2 is a critical step in gene regulation. While DCP2 is the catalytic subunit in the decapping complex, its activity is strongly enhanced by multiple factors, particularly DCP1, which is the major activator in yeast. However, the precise role of DCP1 in metazoans has yet to be fully elucidated. Moreover, in humans, the specific biological functions of the two DCP1 paralogs, DCP1a and DCP1b, remain largely unknown. To investigate the role of human DCP1, we generated cell lines that were deficient in DCP1a, DCP1b, or both to evaluate the importance of DCP1 in the decapping machinery. Our results highlight the importance of human DCP1 in decapping process and show that the EVH1 domain of DCP1 enhances the mRNA-binding affinity of DCP2. Transcriptome and metabolome analyses outline the distinct functions of DCP1a and DCP1b in human cells, regulating specific endogenous mRNA targets and biological processes. Overall, our findings provide insights into the molecular mechanism of human DCP1 in mRNA decapping and shed light on the distinct functions of its paralogs. [ABSTRACT FROM AUTHOR]