Tau tubulin kinase 1 and 2 (TTBK1/2) are highly homologous kinases that are expressed and mediate disease-relevant pathways predominantly in the brain. Distinct roles for TTBK1 and TTBK2 have been ...delineated. While efforts have been devoted to characterizing the impact of TTBK1 inhibition in diseases like Alzheimer's disease and amyotrophic lateral sclerosis, TTBK2 inhibition has been less explored. TTBK2 serves a critical function during cilia assembly. Given the biological importance of these kinases, we designed a targeted library from which we identified several chemical tools that engage TTBK1 and TTBK2 in cells and inhibit their downstream signaling. Indolyl pyrimidinamine 10 significantly reduced the expression of primary cilia on the surface of human induced pluripotent stem cells (iPSCs). Furthermore, analog 10 phenocopies TTBK2 knockout in iPSCs, confirming a role for TTBK2 in ciliogenesis.
Induced pluripotent stem cells (iPSCs) generated from young, healthy individuals are valuable tools for investigating molecular disease mechanisms during the early development of the brain ...vasculature. We generated an iPSC line from peripheral blood mononuclear cells (PBMCs) isolated from a healthy 13-yeard old female donor using the Sendai virus. The iPSCs differentiated into endothelial cells, astrocytes, and neurons. This iPSC line can serve as a healthy reference control for comparative studies in drug development and modeling the early onset of Cerebral Cavernous Malformation (CCM).
The human dimension of biodiversity changes on islands Nogué, Sandra; Santos, Ana M C; Birks, H John B ...
Science (American Association for the Advancement of Science),
04/2021, Volume:
372, Issue:
6541
Journal Article
Peer reviewed
Open access
Islands are among the last regions on Earth settled and transformed by human activities, and they provide replicated model systems for analysis of how people affect ecological functions. By analyzing ...27 representative fossil pollen sequences encompassing the past 5000 years from islands globally, we quantified the rates of vegetation compositional change before and after human arrival. After human arrival, rates of turnover accelerate by a median factor of 11, with faster rates on islands colonized in the past 1500 years than for those colonized earlier. This global anthropogenic acceleration in turnover suggests that islands are on trajectories of continuing change. Strategies for biodiversity conservation and ecosystem restoration must acknowledge the long duration of human impacts and the degree to which ecological changes today differ from prehuman dynamics.
Recent advances in tissue clearing techniques, combined with high-speed image acquisition through light sheet microscopy, enable rapid three-dimensional (3D) imaging of biological specimens, such as ...whole mouse brains, in a matter of hours. Quantitative analysis of such 3D images can help us understand how changes in brain structure lead to differences in behavior or cognition, but distinguishing densely packed features of interest, such as nuclei, from background can be challenging. Recent deep learning-based nuclear segmentation algorithms show great promise for automated segmentation, but require large numbers of accurate manually labeled nuclei as training data.
We present Segmentor, an open-source tool for reliable, efficient, and user-friendly manual annotation and refinement of objects (e.g., nuclei) within 3D light sheet microscopy images. Segmentor employs a hybrid 2D-3D approach for visualizing and segmenting objects and contains features for automatic region splitting, designed specifically for streamlining the process of 3D segmentation of nuclei. We show that editing simultaneously in 2D and 3D using Segmentor significantly decreases time spent on manual annotations without affecting accuracy as compared to editing the same set of images with only 2D capabilities.
Segmentor is a tool for increased efficiency of manual annotation and refinement of 3D objects that can be used to train deep learning segmentation algorithms, and is available at https://www.nucleininja.org/ and https://github.com/RENCI/Segmentor .
Induced pluripotent stem cells (iPSCs) are genetically reprogrammed somatic cells that exhibit features identical to those of embryonic stem cells (ESCs). Multiple approaches are available to derive ...iPSCs, among which the Sendai virus is the most effective at reprogramming different cell types. Here we describe a rapid, efficient, safe, and reliable approach to reprogram human fibroblasts into iPSCs that are compatible with future iPSCs uses such as genome editing and differentiation to a transplantable cell type.
Silver complexes bearing trispyrazolylborate ligands (Tpx) catalyze the aziridination of 2,4-diene-1-ols in a chemo-, regio-, and stereoselective manner to give vinylaziridines in high yields by ...means of the metal-mediated transfer of NTs (Ts = p-toluensulfonyl) units from PhINTs. The preferential aziridination occurs at the double bond neighboring to the hydroxyl end in ca. 9:1 ratios that assessed a very high degree of regioselectivity. The reaction with the silver-based catalysts proceeds in a stereospecific manner, i.e., the initial configuration of the CC bond is maintained in the aziridine product (cis or trans). The degree of regioselectivity was explained with the aid of DFT studies, where the directing effect of the OH group of 2,4-diene-1-ols plays a key role. Effective strategies for ring-opening of the new aziridines, deprotection of the Ts group, and subsequent formation of β-amino alcohols have also been developed.
The generation of induced pluripotent stem cells (iPSCs) from healthy individuals is an invaluable resource as reference control in disease modeling and drug discovery. This paper details the ...reprogramming of peripheral blood mononuclear cells (PBMCs) isolated from a healthy 27 years-old male using non-integration technology. The derived iPSCs displayed typical pluripotent stem cell morphology, the capacity to differentiate into the three germ layers, and normal karyotype. This iPSC line will be used as a reference control to study the Cerebral Cavernous Malformation disease mechanism.
Nitrene transfer: Unsymmetric dienes bearing a terminal hydroxy group can be regio‐ and stereospecifically converted into vinylaziridines upon nitrene transfer from PhINTs using a silver‐based ...catalyst. Stoichiometric mixtures of dienes and PhINTs were employed at low catalyst loadings (0.5 %; see scheme). The method has been applied to the synthesis of (±)‐sphingosine and gave good yields in a three‐step procedure. Ts=4‐toluenesulfonyl.
Several dinuclear terphenyl phosphine copper(I) halide complexes of composition CuX(PR2Ar′)2 (X = Cl, Br, I; R = hydrocarbyl, Ar′ = 2,6-diarylterphenyl radical), 1–5, have been isolated from the ...reaction of CuX with 1 equiv of the phosphine ligand. Most of them have been characterized by X-ray diffraction studies in the solid state, thus allowing comparative discussions of different structural parameters, namely, Cu···Cu and Cu···Aryl separations, conformations adopted by coordinated phosphines, and planarity of the Cu2X2 cores. Centrosymmetric complexes CuI(PMe2ArXyl2)2, 1c, and CuI(PEt2ArMes2)2, 3c, despite their similar structures, show very distinct photoluminescence (PL) in powder form at room temperature. The photophysical behavior of these compounds in liquid solution, solid–solid Zeonex solution and powder samples at room temperature and 77 K have been investigated and supported by DFT calculation. Identification of vibronic coupling modes, done by group theory calculations and the technique of projection operators, shows that the manifestation of these modes is conditioned by crystal packing. Complexes CuI(PMe2ArXyl2)2, 1c, and CuI(PEt2ArMes2)2, 3c, display remarkable activity in copper-catalyzed azide–alkyne cycloaddition reactions involving preformed and in situ-made azides. Reactions are performed in H2O, under aerobic conditions, with low catalyst loadings and tolerate the use of iodoalkynes as substrates.
In the present study, the recovery of valuable molecules of proven anti-inflammatory and antimicrobial activity of the acidophilic microalga Coccomyxa onubensis (C. onubensis) were evaluated using ...green technologies based on ultrasound-assisted extraction (UAE). Using a factorial design (3 × 2) based on response surface methodology and Pareto charts, two types of ultrasonic equipment (bath and probe) were evaluated to recover valuable compounds, including the major terpenoid of C. onubensis, lutein, and the antimicrobial activity of the microalgal extracts obtained under optimal ultrasound conditions (desirability function) was evaluated versus conventional extraction. Significant differences in lutein recovery were observed between ultrasonic bath and ultrasonic probe and conventional extraction. Furthermore, the antimicrobial activity displayed by C. onubensis UAE-based extracts was greater than that obtained in solvent-based extracts, highlighting the effects of the extracts against pathogens such as Enterococcus hirae and Bacillus subtilis, followed by Staphylococcus aureus and Escherichia coli. In addition, gas chromatography–mass spectrometry was performed to detect valuable anti-inflammatory and antimicrobial biomolecules present in the optimal C. onubensis extracts, which revealed that phytol, sterol-like, terpenoid, and even fatty acid structures could also be responsible for the antibacterial activities of the extracts. Moreover, UAE displayed a positive effect on the recovery of valuable molecules, improving biocidal effects. Our study results facilitate the use of green technology as a good tool in algal bioprocess engineering, improving energy consumption and minimizing environmental impacts and process costs, as well as provide a valuable product for applications in the field of biotechnology.
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