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Objective To explore the effects of long noncoding-RNA (lncRNA) taurine upregulated gene 1 (TUG1) on the proliferation and osteogenic/odontoblast differentiation of human dental pulp stem cells (hDPSCs). Methods hDPSCs were isolated and cultured. The surface antigens CD44, CD45, CD73, CD90, CD133 and STRO-1 were detected by flow cytometry. Alkaline phosphatase (ALP) staining and alizarin red staining were used to identify the ability of cells to differentiate. RNA was collected on Days 0, 7 and 14 of the osteogenic induction of hDPSCs, and qRT-PCR was used to detect the relative expression of TUG1. The hDPSCs were stably transfected with a lentiviral vector containing the TUG1-silenced pSLenti-U6-shRNA(TUG1)-CMV-EGFP-F2A-Puro-WPRE to silence TUG1. The ability of hDPSCs to proliferate was assessed with the CCK-8 method. ALP and alizarin red staining and quantitative detection were used to detect the ALP activity and formation of mineralized nodules of hDPSCs. The expression levels of dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP-1), Runt-associated transcription factor 2 (Runx2), osteocalcin (OCN) and osteopontin (OPN) genes and proteins were measured by qRT-PCR and Western blot. Results The hDPSCs were successfully isolated and cultured, and TUG1 expression was significantly increased during osteogenic differentiation (P

Carbon nanomaterials are unique with excellent functionality and diverse structures. However, agglomerated structures are commonly formed because of small‐size effects and surface effects. Their hierarchical assembly into micro particles enables carbon nanomaterials to break the boundaries of classical Geldart particle classification before stable fluidization under gas‐solid interactions. Currently, there are few systematic reports regarding the structural evolution and fluidization mechanism of carbon nano agglomerations. Based on existing research on carbon nanomaterials, this article reviews the fluidized structure control and fluidization principles of prototypical carbon nanotubes (CNTs) as well as their nanocomposites. The controlled agglomerate fluidization technology leads to the successful mass production of agglomerated and aligned CNTs. In addition, the self‐similar agglomeration of individual ultralong CNTs and nanocomposites with silicon as model systems further exemplify the important role of surface structure and particle‐fluid interactions. These emerging nano agglomerations have endowed classical fluidization technology with more innovations in advanced applications like energy storage, biomedical, and electronics. This review aims to provide insights into the connections between fluidization and carbon nanomaterials by highlighting their hierarchical structural evolution and the principle of agglomerated fluidization, expecting to showcase the vitality and connotation of fluidization science and technology in the new era. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are the emerging alternative for silicon for developing miniatured electromechanical devices in the More than Moore's era. But, the inconsistent pitch distances among the aligned CNTs have limited their outstanding performances. Except for the intertube overlapping, the curved morphology is an important but often ignored factor for the attractive CNTs under van der Waals interaction. Here, we have synthesized a clean and curved CNT structure with a definite curvature radius by introducing micro perturbation. Electrical measurement has demonstrated that the curved structure will limit the on/off ratio by orders of magnitude but can maintain a high output delivery in transistors. This is attributed to the resistance induced by the localized strain and the extra current delivery capability of the inner walls, which can be well explained by the energy band diagram model. Among the curved CNTs, incommensurate double walled CNTs of higher diameter difference are the optimal candidates for delivering a high current output by limiting intertube charge transfer. Our demonstrations and analysis have highlighted the importance of controlling both the chiral structures and morphology of CNTs for the applications of high-performance carbon-based electronics. [ABSTRACT FROM AUTHOR]

The self‐assembling preparation accompanied with template auto‐catalysis loop and the ability to gather energy, induces the appearance of chirality and entropy reduction in biotic systems. However, an abiotic system with biotic characteristics is of great significance but still missing. Here, it is demonstrated that the molecular evolution is characteristic of ultralong carbon nanotube preparation, revealing the advantage of chiral assembly through template auto‐catalysis growth, stepwise‐enriched chirality distribution with decreasing entropy, and environmental effects on the evolutionary growth. Specifically, the defective and metallic nanotubes perform inferiority to semiconducting counterparts, among of which the ones with double walls and specific chirality (n, m) are more predominant due to molecular coevolution. An explicit evolutionary trend for tailoring certain layer chirality is presented toward perfect near‐(2n, n)‐containing semiconducting double‐walled nanotubes. These findings extend our conceptual understanding for the template auto‐catalysis assembly of abiotic carbon nanotubes, and provide an inspiration for preparing chiral materials with kinetic stability by evolutionary growth. [ABSTRACT FROM AUTHOR]

Transforming growth factor-[beta] (TGF-[beta]) elicits its signals through two transmembrane serine/threonine kinase receptors, type II (T[beta]RII) and type I receptors. It is generally believed that the initial receptor dimerization is an essential event for receptor activation. However, previous studies suggested that TGF-[beta] signals by binding to the preexisting T[beta]RII homodimer. Here, using single molecule microscopy to image green fluorescent protein (GFP)-labeled T[beta]RII on the living cell surface, we demonstrated that the receptor could exist as monomers at the low expression level in resting cells and dimerize upon TGF-[beta] stimulation. This work reveals a model in which the activation of serine-threonine kinase receptors is also accomplished via dimerization of monomers, suggesting that receptor dimerization is a general mechanism for ligand-induced receptor activation. serine/threonine kinase receptor | subunit stoichiometry

With the increasing applications of nucleic acid aptamers as a new class of molecular recognition probes in bioanalysis and biosensor development, the development of general and simple signaling strategies to transduce aptamer-target binding events to detectable signals is demanding. We have developed a new signaling method based on aptamers and a DNA molecular light switching complex, [[[Ru(phen).sub.2](dppz)].sup.2+], for sensitive protein detection. In this work, we have demonstrated the applicability of this signaling mechanism to small-molecule detection using ATP as a model target. Our results have shown that upon ATP binding to the folded aptamer where [[[Ru(phen).sub.2](dppz)].sup.2+] intercalated, the conformational change or distortion of the aptamer is large enough to cause a significant luminescence change of [[[Ru(phen).sub.2](dppz)].sup.2+]. By monitoring the ATP-dependent luminescence intensity change, we have achieved ATP detection with high selectivity and high sensitivity down to 1 nM in homogeneous solution. The method is very simple without the needs for covalently labeling aptamers or using costly enzymes and multistep analysis as other reported fluorescence/luminescence assays for ATP. The successful detection of ATP indicates that using the signaling aptamers with [[[Ru(phen).sub.2](dppz)].sup.2+] is expected to be a general method for aptamer-based target detection.

A novel method of signaling aptamer/protein binding for aptamer-based protein detection has been developed using a molecular light switch complex, [[Ru(phen).sub.2-]-[(dppz)].sub.2+]. The method takes advantage of the sensitive luminescence signal change of [[Ru(phen).sub.2][(dppz)].sup.2+] intercalating to the aptamer upon protein/aptamer binding. A 37-nt DNA aptamer against immunoglobulin E (IgE) was first tested as a model system. The luminescence of the [[Ru(phen).sub.2][(dppz)].sup.2+]/IgE aptamer decreased with the increase of IgE. By monitoring the luminescence change, we were able to detect the binding events between the aptamer and IgE for IgE quantitation in homogeneous solutions as well as in serum. The assay was highly selective and sensitive with a detection limit of 100 pM for IgE. This new method is very simple and without the need for the covalent coupling of fluorophores to aptamers. The generalizability of the method was demonstrated by the direct detection of two other proteins, oncoprotein platelet derived growth factor-BB (PDGF-BB) using its DNA aptamer and [alpha]-thrombin using its RNA aptamer. This new approach is expected to promote the exploitation of aptamer-based biosensors for protein assays in biochemical and biomedical studies.

Aptamers are a new class of synthetic DNA/RNA oligonucleotides generated from in vitro selection to selectively bind with various molecules. Due to their molecular recognition capability for proteins, aptamers are becoming promising reagents in protein detection and new drug development. In this study, the specific interaction between the protein immunoglobulin E (IgE) and its 37-nt aptamer has been measured directly by atomic force microscopy. The single-molecule unbinding force between IgE and the aptamer is determined using the Poisson statistical method. The individual unbinding force between IgE and its monoclonal antibody has also been obtained and compared to that between IgE and the aptamer. The results reveal the high affinity of the aptamer to protein, which could match or even surpass that of the antibody to its antigen.

Purpose: Three‐dimensional (3D) quantification of circulation using a Finite Elements methodology. Methods: We validate our 3D method using an in‐silico arch model, for different mesh resolutions, image resolution and noise levels, and we compared this with a currently used 2D method. Finally, we evaluated the application of our methodology in 4D Flow MRI data of ascending aorta of six healthy volunteers, and six bicuspid aortic valve (BAV) patients, three with right and three with left handed flow, at peak systole. The in‐vivo data was compared using a Mann‐Whitney U‐test between volunteers and patients (right and left handed flow). Results: The robustness of our method throughout different image resolutions and noise levels showed subestimation of circulation less than 45 cm2/s in comparison with the 55cm2/s generated by the current 2D method. The circulation (mean ± SD) of the healthy volunteer group was 13.83 ± 28.78 cm2/s, in BAV patients with right‐handed flow 724.37 ± 317.53 cm2/s, and BAV patients with left‐handed flow −480.99 ± 387.29 cm2/s. There were significant differences between healthy volunteers and BAV patients groups (P‐value <.01), and also between BAV patients with a right‐handed or left‐handed helical flow and healthy volunteers (P‐value <.01). Conclusion: We propose a novel 3D formulation to estimate the circulation in the thoracic aorta, which can be used to assess the differences between normal and diseased hemodynamic from 4D‐Flow MRI data. This method also can correctly differentiate between the visually seen right‐ and left‐handed helical flow, which suggests that this approach may have high clinical sensitivity, but requires confirmation in longitudinal studies with a large cohort. [ABSTRACT FROM AUTHOR]